Help? ¿miniskirt on period?

I'm gonna start a girl in September and the students have to wear a uniform. For the girls it's a miniskirt along with something else but let's "Focus" on the "Miniskirt" and tbh I'm scared to go to the school on my period and have to wear a miniskirt.. I can't wear a tampon my mom doesn't want me to so I'm stuck with a  pad AKA the 'Adult Diapers' I'm scared to leak.. I'm so insecure it's just I'm just scared.. In my current school it's no big deal cuz the skirt is knee length and it's an all girls school and idk if I leak cuz they won't laugh they'll understand it's a normal thing I know that cuz I've leaked once but I covered it with a sweater around my waists.. So tell me do you have any advice for me to go to a MIX school with boys and girls... BTW THIS IS AN EXAMPLE OF HOW THE LENGH OF THE SKIRT