advice needed

GF
Advice needed !!!
So I had a misscarrage on the 15th January I stoped bleeding 21st January my second period started 6th February till 11th Feb 
Then my 3rd period started 8th march (4am) till 11thmarch  it started heavy bleeding and got lighter Saturday 8th I've never had a 4day period should I be worried what could it be ??