Could I have endometriosis?

I have an appointment next month to see a fertility specialist as me and DH have been trying for a year with no success. I have regular periods and mild cramps but nothing terrible. There is pain during sex but only in certain positions such as doggy. In missionary or me on top there is no pain. Could I have endometriosis if that is my only symptom? My appointment feels so far away and I just would like to know if there is a chance I have it and that’s why we haven’t conceived yet. But I don’t know if you can have endometriosis with pain during sex in certain positions or during all sex and if my cramps are nothing bad