Should I take a chance with this guy or run like the wind!

I met this great guy about six weeks ago. I went out with some friends of mine and one of them introduced me to their friend Joe :-). My friends werent really intending on him and I hitting it off, so a couple of my friends mentioned that they had slept with him. Joe and I ended up hitting it off and found that we have ALOT in common. Things are starting to get more serious between the two of us and we’ve talked about being exclusive. Last night we were talking and he mentioned that before me he hadnt had sex with anyone in over a year. He obviously didnt realize that my friends had told me before we had even met. I didnt tell him that I knew differently. Im doubting getting anymore serious with Joe because now Im doubting everything he has told me. Should I get the hell out!! Or is it possible that maybe he was ashamed? Any advice?!?!