Painful sex

Vicky

So I got checked for std on June 14 and was negative and got checked again two weeks ago and was negative. I had sex today (SAFE) but it was uncomfortable I haven’t had sex in such a long time. I think that the sex was uncomfortable because I was in an uncomfortable position and never had sex on a bed and this was my first time having sex on a bed. But to you lovely ladies why is sex painful for me.