Help!!!

I was just wondering if anyone's experienced the same thing, or if someone would know what it is. I've been with my boyfriend for the past 2.5 years and just in the past month sex has been very painful. We use enough lubrication and foreplay. It feels like I'm extremely tight. I had a Pap smear 4 months ago and it was normal. I also took a pregnancy test 2 weeks ago and it was negative. Any feedback would be appreciated! Thanks ladies!