Missing. Period

So I am 45-51 days late lol starting in October my period starting coming on every other month . I haven’t had my period since January 12th-17 . Since I knew my period was going to skip February I wasn’t really worried about it .. well here I am at the send of the month and it’s no period. But the thing is I been spotting and having cramps off and on . But never a full blown period and my emotions have been everywhere . I’m asking you guys because need help also I took a pregnancy test Friday and it said negative with a bold line .. so I was kinda sad ...