I would go with an allergist. They have degrees
in immunology, and can get to the bottom of it.
In the meantime, please be careful - reactions can get worse. It happened to me, and all the while my docs gave me prednisone, and told me probably food, detergent, etc. Well, it got so severe (whole nother story) and ended up being a med I was on. The very ones they told me weren't likely to have allergic reaction.