My Period Was Suppose To Come On The August 5

My period was suppose to come on the August 5 but it didn't and on August 16 I went to the bathroom I peed and when I wiped myself on the toilet I saw light pink blood then on the 17 and 18 I was bleeding but only small amount , and today on the 19 I'm back to just spotting and I get a sharp pain on the right or left side of my stomach what does this mean ? And I just been sleeping to much all I what to do is sleep