Is it bad for me to↓read! No boys, Only girls!?

Ok everyday i run a bath and sometimes which is most of the times i open my legs to the water that comes out well down and i Guess you can call it masturbating and i like the way it fells but after i began doing it it hurt my "" badly it would make it sting but i haven't told anyone and ever since i started water or pee just leaks out of me and i have not had my period yet i am 12 and i have not had it at all so leaks scare me so i look and it look like i guess mucus in my pants or white sticky stuff and i get really scared so i just asked my mo about that if it was Natural that i get that white stuff she said yes its a sign that your period is coming and that made me fell better but it happens some seconds and i need to know the answer to this for real!! i thought the white stuff was sperm but i need only girls to answer this!!