Please suggest

Hi,

I got married in 2016 and I am trying to have sex with my husband. When he is trying to insert his penis, it is not going inside my vagina.

We are trying a lot. I even applied lube but when he is trying to insert his penis it's hurting me a lot and I am pushing him away. I get my period on time. I don't know what is the problem with me.

Is there a problem with me ? Please suggest me some ideas.

Appreciate your help

Thank you