Why is this happening? Is this my period cycle?

okay, im 14 years old and ive NEVER had my period yet, but yesterday wen i woke up, i went to the bathroom and went pee, then wen i wiped there was a bunch of blood on the toilet paper, and i kept wipping, with a different sheet, and the blood was less and less untill there was nothing left. (i told my mom but she didnt really say anything bout it, just to wear a pad just incase) but i didnt put on a pad. so then a few hours later, i was sitting watching tv, and i felt kinda wet. it felt like discharge but it was alot. so i went to the bathroom and cheaked and there was a huge blood stain on my underwear! so i finally put on a pad but ever sence then, there hasnt been any sign of blood.. wat does this mean? please help!