Thyroid issue and MC

Nicole
I'm hoping someone may have some past experience with this. I haven't had a thyroid issue in the past. Quick rundown of my history:
​January I had full physical- TSH 4.21. Still within normal range but dr wants to follow up in 6 months bc it is on the higher end.
​Feburary: 1st month trying...get faint positive but blood work shows hcg is only. 15, start miscarriage early March. 
​June: my periods are finally back to somewhat normal although I'm spotting for 5 days after normal flow period. I have a b12 deficiency (I don't absorb it) so I made an appointment to talk to dr about apotting, recheck thyroid and get b12 shot. 
​Today: nurse calls with TSH results...my TSH is LOW. I can't remember the exact number but it was .4 or .04. The nurse even sounded shocked when she realized the major difference. 
​So I head in to have antibody tests, immunoglobulin tests and t3 and t4 tests done tomorrow. 
​Does anyone have any ideas or experience? I'm heartbroken and convinced it will be impossible to conceive now. 
​Thanks in advance