Hi I'm 23 y/o. I am 3 days late on my period... and today I realized a slight brown discharge . I been having stomach cramps , for about 5 days now , but still haven't gotten my period. I'm on a normal 25 day cycle. When I went to my doctor about a week and a half ago she told me I'm due for my period by 3/18 and its now 3/20.. I been really tired lately.. all I want to do is sleep.. I took a hpt but it came back negative. I was wondering if anyone can help explain what is going on

2 or 3 days late isn't really anything to be worried about, take another test in a week or two, but you might even miss a month, this is very common.