Need SERIOUS Advice. Not a marriage question but a relationship question.?

Me and my guy friend were platonic friends for almost three years. During that time he had a girlfriend and they broke up officially about three months ago however he continued communicating and sleeping with her (unbeknowest to me) anyway during that same three months we began dating and growing closer. Although we did not and have never slept together we were pretty intimate in conversation and getting to know each other. About a week ago we decided to establish ourselves as an official couple and that for me is where it all began to go downhill. Although we get along fine immediately after establishing ourselves as a couple my intuition kicked in and keeps telling me that this relationship is not going to work out. I have never really been in a serious relationship so I don't know if this is new relationship jitters/awkwardness or is my intuition trying to tell me something. I continuously second guess whether or not he really likes or am I just there to fill a void. I want us to become intimate and know that he is attracted (as am I) but wonder is that all I am there for. I am sooo confused. I like him but put an exorbant amout of pressure to feel like I need to do everything not to rock the boat. What is wrong here? Please help!!