Longer than usual! Help!


So my period has lasted from last Monday to today (8 days) and idk if that’s normal, is it? I have my graduation of primary school on the 20th(it’s the 17th today) and I don’t want my period at graduation can you stop a longer period? If so how?

P.s I’m only 12 and don’t have access to most medicines I’ll have to ask for them