narmada thanks for the advice. Today has been different and I was beginning to doubt myself, thinking I'd been bothering everyone for no reason (4 5oz feeds, no crying during feed, though some difficulty with crying and very little sleep throughout most of day) and now feel a little guilty that DS cried at start at bedtime feed to show I do have reason to be concerned.
I don't think he has any real issues with vomiting (is generally not a sicky baby at all, very little possetting) or diarrhea or constipation (though the comfort milk has not made stools thinner as it warns but thicker and more solid and generally only poos once in two or three days now, whereas it used to be once a day) so I don't know what to think. The comfort milk does appear to be helping as he isn't crying or upset as many times or for as long as he used to be (thank goodness!).
IMO the only reason he is maintaining a reasonable weight gain is because every few days his feeds are at 5oz and then they often go down again. The HV was surprised when I said he was only taking 3oz a feed most days and wasn't having more than 5 bottles a day but didn't say anything other than "well he's gaining weight so everything must be fine", which as other people have mentioned, is often the very sad case when something is wrong :( I also have slight issues as DP often joins in with the HV in saying I just have to persevere or thinking that he isn't hungry because he's crying and appears to be fighting the bottle, he then gets understandably annoyed and upset and so I often end up taking over and then DS takes it from me, probably upsetting DP further :(
Have you find that once they settle to feed after crying and fighting it that it is often a sleepy feed?
If he's content he goes down fine in his cot or on the sofa, if he's having his little episodes of crying and pain and whatnot you can't put him down or he starts screaming or crying loudly, arching back and stretching legs and clawing at your face. This also happens a lot if you sit down with him instead of standing up
I've also decided to keep more details, other than just times of feeds and sleeps and whatnot in the Baby ESP app I have for my phone, so I can keep track of crying feeds and crying sessions and good sleeps and bad and everything, and can back up everything I say to GP and HV in future. The new bottles have made no difference so it is not the birthmark that is causing the crying feeds (they really did help when we changed last time though, and the time may come if they don't sort the birthmark and it keeps growing, that we need the new ones I bought) so we definitely need help
will keep you posted.
p.s. any good sites with info about CMPI?