Solid foods and bad gag reflex

My son Jaden will be 7 months old in 5 days, almost 2 months ago i introduced him to solid foods. Starting off with just the Gerber rice cereal and working slowly mixing peaches or bananas in it. And he took to it like a pro! He was on a roll up until about 3 weeks ago, He gets excited when he sees the bowl but then cries and gags when i start to feed him. He even gags with the bottle so i have to watch when he's feeding otherwise everything he has drank will come right back up w/a gag. I dont know whats going on and im worried, cause he loves his food. My mother says its a textural problem, but what i dont get is why he was doing so well and now all of a sudden develop this problem. Am I doing something wrong? I love my son and am open to any suggestions or info...