T.B.
You MAY have been on the right track thinking about allergies. "I haven't eaten anything else funny". My son was the same as an infant (red cheeks) and once I started him on solid foods it was quickly obvious he had many food allergies. One of his first foods (after cereal) was avocados and he had an immediate allergic reaction (vommit, hives, facial & neck swelling). Although there is the "top 8" (the most common food allergies in the US) you can be allergic to almost any food and many foods are in the same "family". Anyway, keep allergies in mind. If that seems to be the issue www.foodallergy.org is a great place to get info.