Gavin has food allergies

It seems Gavin is going to have various food allergies. I mentioned that he had a rash after eating homemade sweet potato puree but today he had a similar reaction to jarred baby food-apple sauce. I honestly thought my mom was exaggerating when she mentioned the allergic reaction to the sweet potatoes. But after seeing the reaction myself after he ate the applesauce, I was a little scared. I immediately googled baby food allergies and then I was REALLY scared when it mentioned that if there's swelling outside there can be swelling on the inside which can make it hard to breathe. I'm already paranoid of him not breathing- Nick makes fun of me b/c I put my hand on his back while he sleeps just to make sure he's breathing. I was slightly relieved when I read that usually when that happens (swelling of the trachea) the lips are also swollen. Gavin's lips were not swollen. Actually the reaction seems to be concentrated on the right side of his face. His right eye was swollen almost shut and the area around the eyes and his cheek was very red and covered in small bumps. We've eliminated any other possible allergens given that nothing else changed other than the food AND the reaction only occurs after he eats the food.
I called the pediatrician's office to find out if there's something I should do outside of obviously not feeding him the food. It's 3:30pm and I still don't have a conclusive answer. I've spoken to the nurse 4 times today. The nurse asked me the expected questions: have you used any lotions, soaps on his face?, did the reaction happen immediately after eating? what type of food?, any other changes in behavior, breathing patterns? etc. Until further notice, Gavin is strictly on a rice cereal and formula diet. Given the reactions, I will be making my own baby food when it's ok to do so just so I know that he's only eating the natural fruit and vegetables and can rule out any additives that may be in the baby food. He did well with pears last week. What I read online says it's not abnormal for a baby to have a reaction to something he has eaten in the past. Which makes me question everything. So I'm sticking with the rice cereal until the doc can give me a straight answer.