Yesterday i ate somthing with gluten in it and then my throat started to swell making it hard to breathe. was this an allergic reaction?

Allergic: Gluten intolerance does not affect your throat. You need to consult an allergist to find out what is the ingredient in that something which caused your throat swelling since gluten was not it. In addition you need to get an epinephrine autoinjector pack for emergency ASAP since you may not be that lucky next time around,

Can be separate issu: Gluten is a collection of related proteins found in certain plants. It is well known to trigger a delayed reaction (days/weeks)like a virus where the body forms antibodies that attack your gut & maybe other tissues. What you describe is a rapid/emergency allergic response to that food that can be separate from any gluten issue. You need to consult with your doc or an allergist. Avoid that food.

Throat swelling : Yes this could be and you should follow up with your doctor for further management

Yes, but not gluten: Gluten sensitivity does not cause this type of allergic reaction. You should write down all the other ingredients in the meal that you ate to help your doctor when you have your evaluation.

Mgt.: I would also advise listing all ingredients so that the food allergy testing may include these specific allergens.