I'm allergic to fish, but before I found out about my allergy, fish used to make me feel sick. And I've never liked the taste of fish either.
Lyme is known to increase one's risk of developing food allergies/sensitivities and/or intolerances.
If you suspect fish allergy, avoid all fish and fish-derived products for 2 weeks, then try something with fish in it and see what happens.
It's possible it is only one kind of fish that bothers you, too - for instance, I've heard of people who are allergic only to shellfish (lobster, crab, mussels, etc.) and not other kinds of fish (tuna, salmon, cod, etc.), or visa-versa.
Also, next time you feel your stomach being upset by fish, try taking Benadryl or some other antihistamine and see if that helps...
I hope this helps...take care,
Chronic Lyme, Bart., Gluten & Sulfite Sensitivity, Many Food/Inhalant/Medication/Chemical Allergies & Intolerances, Asthma, Gut dysmotility & non-specific inflammation, UCTD, Osteoporosis, etc.; G-Tube
Meds: Claritin, Singulair, Domperidone, nutritional supplements, homeopathy, probiotics, etc.