Food Allergy, GI Issue or Histamine Intolerance? Maybe something else?

[Jsali]

24 - Female

4 Months ago, I had the experience of after eating(Meal: Cheeseburger), I immediately had strong painful cramps around my belly button an below. (These pains would make me lose breath, bend over ect) I then needed to use the bathroom an experienced painful lose bowels and Nausea. Then broke out in HIVES and swollen lips.
I attended the medical centre whom advised "Its a reaction but don't know what of" and provided me antihistamines for 3 days.

2 weeks after this, I had a repeat episode (meal : Ikea Meatballs and Steamed Veggies) although the hives and swelling was much worst! I attended the hospital, whom provided IV Antihistamines and no further advise or referrals

1 week later, after having coffee and cake (about 60 minutes later) another episode although with the added dizziness and ears felt blocked and blocked nose. I attended the hospital, whom provided IV Antihistamines and no further advise or referrals

I really had enough of all of this so I told my GP that I wanted further testing. Which the GP refused as I am currently breastfeeding (apparently breastfeeding means that you cant have allergy testing ect) instead I am on 24hr antihistamines daily.

Being on this medication daily has helped the episodes but hasnt stopped them. Its makes the hives much less and the episode isn't as bad and doesn't last as long.Since starting the medication I have had a further 3 episodes. Although I am finding that now after eating almost anything I have to use the bathroom immediately and I have cramps around my belly button and just under my diaphragm area.

I am usually a very private person, but I really need advice. Have you experienced this before? does it sound like something you know of? What sort of doctor should I be asking to be referred too? (considering my GP isn't helping)