Could Missing Periods Be Due To Pregnancy?

Hi , I'm a women 22 years old getting married 5 months ago I'de gain a lot of weight
My last period was on august 2nd I had five home pregnancy test they came out all negatives I went to the doctor she said maybe it's a thyroid I get some tests and they send it to me today they said my thyroid hormone is normal . And I have a low vitamin D and maybe diabetes . But I still not having my period can I be pregnant ? thank you