Back to back miscarriage

Today I went to the doctor because I had two back to back miscarriages. They did a transvaginal ultrasound and blood work. My doctor came in and said it looks like there is no remaining tissue and my uterus looks healthy. She is confused why I keep having miscarriages because my first born son (first pregnancy) was healthy. She put me on baby Aspirin and a high dose of Zoloft 100 MG for depression (scared to take because I want to TTC) she said if I get a positive test to message her and she can put me on progesterone... does baby aspirin and progesterone work?? Anyways she told me to wait until a cycle... why?? I wished I could start trying now 😩😭