Is the doctor basing his opinion only upon the fact that the child vomits and refuses food or is there any physiological evidence that might suggest that she is unable to swallow? Many babies with food allergies
are late eaters and vomiting is the body's first rejection of something that isn't right. Some babies have a mouth full of teeth at 8 months and are big eaters others, like yours, have 2 teeth at 10 mos, and little interest in other foods. If she is nursing, gaining and in, I believe it is best to respect where your baby is at and likely there is no reason to be concerned. How do you feel about her eating? What is your gut feeling?
Because you have food allergies
, she is predisposed to them as well. If you are allergic to banana, she may be also. I will add though that it is possible it was the rice cereal that constipated her because of the added iron. Rice cereal is a filler food and really offers little in nutrition. Fruits and vegetables offer more vitamins. Also. be happy she isn't eating Cheerios which are mostly starchy and sugary and not much else.
As she gets older you will be able to try intoducing foods again. And it looks like you are already observant of reactions in her so likely you will be able to detect anything that doesn't agree with her. Just be patient and enjoy not having to prepare those uneaten meals while it lasts!