Need advice

So I had a miscarriage on January 22ns got my period on February 25th had my period for 6 days which isn’t normal but figured it was cleaning everything out. Went to my Obgyn to get checked and he said everything was fine. I was due for my period on Wednesday and NOTHING!! I’ve taken 2 pregnancy tests there negative. I have had symptoms like mild cramps here and there. A headache and backache but still haven’t got it. Has anyone had a miscarriage and got there first period then skipped a period after that? When I was pregnant with my son after I had him my period went back to normal in 5 weeks got my first period and every period after that was normal. So I’m not entirely sure as to why this is happening?