Tired of fertility treatments

My husband and I have been TTC for over 4 years now and nothing. I have never been diagnosed with anything that could be preventing from me from being pregnant. We started fertility treatments last year, taking clomid and trying the IUI (insemination) twice and the 1st time I got pregnant but had a miscarriage soon after. The 2nd time all signs pointed to everything working out and nothing :( I am at my whits end and don't know if I should continue to see the same fertility doctor or should I search for a new doctor and try Fermera?? Any advice??