Concerned NEED HELP

Nya

I’m in high school and I just lost my virginity to my bf I’ve been with for 2years we had sex Tuesday 4x and Sex on Thursday 4 times unprotected he pulled out and I’m on the depo shot but I woke up this morning and I had a lil but of brown spotting (this is also the first time I’ve had sex be on the depo) I’ve been on the depo for almost 2months now should I be worried or is this Normal?