Period after baby

Sandra
I had my baby on May 7th, I got my period on July 4th-9th and then again on July 20th-24th and august 1st-5th. I haven't had any bleeding since then though. Before I got pregnant I was never regular so I thought that I would be regular now since I got my period two months in a row.  I did take a pregnancy test and it was negative. I just wanted to get others opinion about this.