Young & cant conceive?

Hey Glow family! Never really posted on here but here i go! Im 21 years old and have a 26 year old boyfriend. We have a great relationship but one things missing. I wont get pregnant! He always tells me how he wants a kid(he doesn't have any) we've ben trying for 2 yrs but NOTHING. Am i not able to conceive? I dont see why i wont get pregnant? It makes me sad when he asks if my period came hoping it doesnt. Any help or advice??

By the way i know im young but I've ben through ALOT in life & is more like a 30 year old than a 21 yr old... I dont even have friends my age lol thanks for taking the time to read this