Spotting After Walking.

So like three days ago I had brown spotting that was light at first and got a teensy bit heavier then clotted. It stopped after two days but now it’s back after I walked around (maybe two miles) with my friend. It was enough to transfer on my underwear where the spotting before was only when I wiped. My discharge changes between gray and yellow/brown. Now that I got home I have painful cramps. My mom says there’s no reason to go to the hospital if they can’t do anything for me. Any help? (I’m only 16 hence why my mother is involved) my appointment isn’t until another week and a half