Advise..

My boyfriend and I been together for 7 months now, and he's a lot older than I am. I got a call a few weeks ago calling that I tested positive for chlamydia. But he was the only one since we got together. But back in March in the beginning, I was raped but I got tested within that week and everything came back fine. Now my question is...is my boyfriend lying to me about sleeping with others or was I carrying it and not knowing it?