No underwear on period?

sandy • a libra angel ✨

Yesterday my period started but i haven't been keeping up with the dates and i went commando. I didn't realize that I had it until I peed at about halfway through the day and there was blood on the paper. This seemed weird to me, considering that i had no panties on. So i went to sleep with a pad on. I wake up, it's soaked. So today I'm home all day and I'm not wearing underwear again, to test this whole thing and ik it sounds gross but again, no blood. I peed and wiped and there's blood on there. What is going on? Is this what free-bleeding is? How is there not blood coming out of me?