HSG and Femara

Sarah
Hi ladies! I need support...I'm 25 years old and my husband is 27. We have been TTC for 16 months. We are both healthy people, we are both at a good weight, eat right, don't smoke or drink and I have regular periods. And my husband has good sperm.I have been on 3 rounds of clomid, and each round I have ovulated. My first round I had 1 follicle, the second I had 1 on each side and the third I had 1 on one side and 3 on the other. My doctor said on my last ultrasound sound that my lining was pretty thin 4mm. She said that's because of the clomid. Last night AF arrived, and I'm so upset, trying not to lose hope. 
So now my doctor is wanting me to start Femara, and get an HSG. I'm really hoping that this will do it. Have anyone had success with Femara compared to Clomid? What about after an HSG?