Brown stuff in my underwear?

I'm 12 and I haven't had my first period yet. 3 days ago I had dark brown booger-like things in my underwear and a patch on brown stuff that felt not wet, but not dry, kinda moist? And when I wiped after using the bathroom, there was a little bit of blood. And 2 days ago there we're no booger like things just the patch and same with yesterday and today. I'm wearing panty liner and it kinda looks in between red bean paste and poop. I don't know if it's my period or not. Please help? It has no odor and I asked my mom, my sister, and my best friend and my mom and sister said it's my period, and my bestfriend said it there was something wrong/I had an infection. My sister said that the boogery stuff was a discharge but i just want a answer I can trust. Helpp?