hi mrs d you first. i think that maybe sometimes you are depressed and that when you are tired it makes everything you are going through worse, mainly because you aren't rested enough and therefore don't have enough energy to be able to "cope". i think your dh speaking to hv is definitely a v.good idea, for some reason, some men seem to take more notice if things are pointed out by another impartial 3rd person. so good for you for sticking your foot down
and (((hugs))).
i'm glad your ds slept longer, the only thing that could get my dd to sleep longer was to give her a nice warm bath, followed by a massage. you don't have to give him a proper massage, sometimes just rubbing their legs and maybe their arms too with some of that baby oil gel stuff by johnsons (it has chamomile in it) or anything like it will do. then half hour or so after the bath, give the last bottle of the day, maybe read a story, then when he really snuggly, and his milk gone down, put him to bed saying time for bed in a soft voice, possibly repeating yourself several times. you might have to go back in a few times but eventually, hopefully, he will get used to the bedtime "routine" and even ask to go to bed. bear in mind though that this is what works for dd and it took a while to get her into this routine, but it does work 99% of the time.
i'm glad your dd had a brill time at the farm! 
please still make the gp appointment though, maybe you could write down beforehand what you want to tell him/her so that you don't forget anything? perhaps make a double appointment so you don't feel rushed. please tell him the truth, they won't be shocked, and then you might be able to feel a lot lighter.
hth, sorry for long post. love fm x (((((hugs)))))