Trying to convince, 2 pregnancy loss.

Last year on 12th of May I got known that I was pregnant, but i suffered a miscarriage on 22nd May. That pregnancy wasn't planned but  consulted a doc, got to know that my thyroid was 4.2mul, vitamin D was 12 and through usg I got to know my endometrium was 5mm thick just two days after miscarriage. I was on medication like Evecare, Native, thyroxine, apfol, bactoclav, Depura D. But after few months I stopped taking medicine completely, from March we were trying to conceive on 23rd of April I got know I was pregnant but from practo app only I consulted a doc she told me to go for repeated hcg test which reached 356 till 11th of May, again I was told to go for usg in which I found my Endometrium is 6mm, from 15th only my bleeding started I was shattered as on 27th I got my thyroid test done it was 9. I was taking 50mg of thyroxine, susten 200 mg and folic acid 5mg. 1) Is my uterine lining is causing chemical pregnancy? 2)should I go for TVS? 3) how early I can conceive?