I'm sorry you're feeling in pain and confused by your symptoms and that you're being dismissed by health professionals.
I'm not a medical professional but I have had miscarriages, and I found unfortunately after a pregnancy, no matter how short, it can affect your cycles for a short time. Just as they say you can be more fertile for 3-6months after a miscarriage, this must mean it has some effect on your cycle / hormones.
For me, I did notice more cramping around my period due date, and the bleeding heaviness pattern changed too. I was emotional but this was more to do with my grief and infertility journey, but I suppose could have been exacerbated by my cycle.
This could be linked to a change in hormones which could affect emotional or mental symptoms too. If these symptoms are related to your cycle only, then it may be in a few months, things settle and your usual cycle and symptoms return.
For now, I'd try focus on ensuring you are eating a well balanced diet, drinking plenty of water, getting exercise, taking folic acid if you want to continue trying to conceive and just looking after yourself as best you can. If after another 3 months you don't see an improvement ask your gp to look into it further and let them know what you've been doing in the meantime and ask for tests - either blood tests related to fertility / hormones throughout your cycle or for more general things eg anemia, thyroid etc.
I hope this helps. Happy to talk if you need it x