spotting ?

hello everyone , i got married a month back on 2nd April 2007 and 19 years old . Actually i had gynococid and had periods on 9th april wheras my date was 13th . I got spotting 4 days back which means 28th April and still i am having it . I got my pregnancy test but it showed negative there was no pregnancy. Can you help me about this ? What all is happening to me i'm really worried.
Please...