I know I shouldn't ask for an internet diagnosis and I WILL be encouraging DD to speak to GP but just need some idea of where to start, how to make sense of what's going on! Sorry to be brief but so much to say and I'm not sure how to get it all down;
DD (18 now) has always been a little bit highly strung and had issues with certain things for a long time - we didn't so much think she'd grow out of it but grow up to have more coping skills and it's not happening, she's getting worse and worse. When she was about 8/9 we spoke to GP about concerns and got referred to paed who said she may have sensory processing disorder, due to a fair few things which ticked those boxes, such as fussy eating, problems with clothing, problems with noise etc but they were "anxious not to give her a label" and suggested just having school and home work round her so nothing much more was really done.
Since then to now DD has had less problem with those sort of things but her behaviour is way more erratic. She has more and more 'tantrums' for want of a better word, they're definitely not 'meltdowns' in the way I've always seen them described but more than just a teen strop, maybe halfway between the two? They always seem triggered off by changes, not big changes such as moving schools etc, she seems to cope quite well with big changes, it's tiny things that set her off (although maybe it's a 'straw that broke the camels back' type thing?).
Eg, today we were baking together and everything was fine until she dropped some egg on the tablecloth and I started moving everything off to put the tablecloth quickly in the washing machine (I wasn't cross in the least or anything) then popped it on for a quick wash before the egg dried. DD normally does the laundry as one of her chores but I didn't mind putting this on as it was an emergency. DD got really stressed though when she saw I'd put it on saying she should have been the one to do it and I should have asked her to do it. Then she got cross again 5 mins later because she left the end of a banana in the skin when peeling them and I saw, popped it out and put it in the mixing bowl with the rest, she got really annoyed because I was 'messing about with the mixture' (that's genuinely all I did).
Big crises can come and go without any more stress than anyone else would show but these tiny things seem to really set her off. She was really agitated and started being really rude to me, I tried to calm her down but then had to tell her not to be so rude but she worked herself up more and more and got completely 'stuck' (she wouldn't finish off the cooking, wouldn't stop being rude so we could do it together, wouldn't let me finish it, wouldn't throw the whole thing away, wouldn't choose if I gave her a simple 'either or' choice to avoid her being overwhelmed).
In the end she got so worked up she was yelling at me and chewing on tissues, literally staring at me blankly shoving tissues into her mouth as if she was eating them. She's not done that before but has done other stuff like sit banging her head against a door or ripping a cardboard box into tiny pieces for ages in frustration. In the end she finally agreed to go up to her room to calm down because I said I'd phone 111 for help if she couldn't calm herself.
I don't know what to do, her moods get more and more volatile and to sounds horrible but I can't even tell what's bad MH, what's laziness and what's drama just to get attention tbh. Some times she's lovely and sweet, more often she's really depressed and sometimes she's in these explosive moods.
She's got no friends, literally none, isn't bothered at all about getting a social life or doing much outside the house except walks, and sleeps and eats erratically despite everything I say/suggest to try and change it. She's basically 'unlearning' common sense, even things she'd handle a couple of years ago now seem beyond her, and any setback makes her either furious or really depressed.
Covid has definitely made it worse too, she pulled out of A-levels a month before finishing because she was so depressed but since then hasn't really felt any better. I should push her into getting a job but she's not keen because of covid and tbh I'm not sure she could handle a job.
DD has said before she thinks she might have ADHD, I think maybe that or she has some signs of autism but nothing seems to fit completely. She hates the idea of going to GP or counselling but I'm not capable of dealing with this by myself, I'm not arrogant enough to think I can help DD all by myself and she's resisting me trying to help even if I thought I could!
I deal with these flare ups as well as I can, probably not that well, but I'm really struggling - I have anxiety myself, DH has depression and tbh our whole blinking family is a mental health textbook so I'm feeling like the base of a flimsy house of cards most days. I don't know how to help DD.
I'm not even 100% sure what I'm asking tbh but can anyone help me with wtf I'm supposed to do.