Do i need to see a doctor plz help????

For the past probably month and a half i have been some what overly bloated and gy and i cant really explain I thought it was just indigestion or buildup so i eliminated caffeine from my diet. I am not allowed to eat most chicken,pork,ham because I am allergic to some of te preservatives that they contain. In addition, I am lactose intolerant so my diet does not consist of dairy. Anyways, I have just felt that my food is not properly being digested and it feels like its getting stuck, which could explain the bloating. However, for the past four weeks my poop has changed one day im very consipated the next my poop will form like pebbles and sink then the next day it will float. I am very concerned because I have no idea whats wrong please Help!!!