Am I normal?

Had sex last night with my husband. It was great until he finished and I didn't. I tried to finish myself for what felt like forever and it didn't work. I immediately started balling and I've been pretty depressed since. Since having my child 18 months ago I find it hard to get aroused and when I do, even with a lot of foreplay, it's nearly impossible to orgasm. Is this normal? Any suggestions?