Period just started

Ok so I’m like the late bloomer in my family to start their period and I’m 15 I’ll be 16 in September. Its 2am and i go use the bathroom not expecting anything. But i had diarrhea (sorry tmi) but i go to wipe and there’s blood . I told my mom and she said ok so i take a shower and there’s no blood . I need help i put on a pad but I’m not for sure , the only reason i said i started my period was because I’ve never bled while using the bathroom . But yesterday around 3 pm i was feeling good but i thought nothing of it anyways somebody just help me.