Depo shot

I got the depo shot May 8th 2025 and didn’t have a period for the whole month of may then it went to June almost the whole month no period but June 23rd I started spotting like when I wipe i would see it on the tissue real light just a drop & a brown color . Nothing was in the toilet just on the tissue. So that was Monday today is Saturday & when I wipe it’s still there . Just scaring me this my first time on the shot and I go back for 2nd dosage end of July beginning of august. I’m just scared I don’t want to be bleeding for months . Hopefully it stops by Monday. HAS THIS HAPPENED TO ANYONE?