Its Been 60 Days Since My Last Period. My Cycle

its been 60 days since my last period. my cycle is usually varies from 30 days to 45 days. I have done home pregnancy test as well as got my blood test done. all test are negative. I get on and off cramps in my lower abdomen the same type which i get in my periods. Out of curiosity I am still checking my pregnancy one and the other day. I generally get my periods only for 1.5 to days. I am gaining weight like anything. My thyroid, sugar all came negative. Not getting whats going on.