I havent gotten my period for 38 days....?

the first time I had my period was in September, and only for the first cycle, was it ever as long as 38 days in between each one. im 14, and the last period I had (38 days ago) was only for four days. it was very light, well not really. first two days was pretty heavy, but the last two days were pretty light, like ok ish. and the fourth day was rly light. before my last period, I had ran 10km for this marathon thing. but I remember my vagina kinda swiped the shower curtains shortly before my period. and since the four day period, I haven’t had another one. it’s been 38 days, and since two days ago, ive been getting brown discharge. is it old blood? my period? or is there something wrong with me? im really worried. could I be pregnant? (ive nvr had sex, but my vagina swiped the shower curtain, which COULD have some semen from my bro or something?) or do I have like some disease? or is it ok? cuz in 30 days, I am going to camp, and I don’t want to have my period then, so is there something wrong with me? thanks.