Possible sudden food allergy?

[KaiRich]

Lately I have been getting allergy symptoms from certain foods. First it started off just from milk chocolate, my biggest vice. So it's not as if I stopped eating it or something and suddenly started back up again. I have never had a allergic reaction to anything before this, but my throat got itchy, it felt bumpy, I couldn't stop coughing. Now about a week later, it has progressed to practically anytime I eat, and I keep having to throw up my food because my body just won't digest it half of the time. I have gerd so I just thought I was having a bad day but it has gone on much longer than it should. I am suspicious that it might be dairy but butter and plain milk seem to be fine. The reaction isn't super serious yet, more uncomfortable at this point but I fear that it will get worse.
To narrow it down until I am able to go to the doctor, is there any other foods/ingredients I should try to avoid?
Is there any certain tests that I should ask for?
Should I go to my PCP or try to schedule an allergist?
Are there any triggers for a sudden allergy to pop up?