I fear I am infertile

Okay I'm 22 and am sexually active I have a boyfriend we have been together for nearly 5 months we have unprotected sex regularly and before him I had a lot of unprotected sex with my ex and before that with other guys ( dumb I know) but I have never in all the years been pregnant and I fear in infertile I would like to have children one day in the future and would be gutted if I couldn't. I'm not trying to get pregnant at the moment but is it silly to try and get some sort of fertility test at the doctors for peace of mind??