My upper bum crack is really really really itchy?

guys, before you read this question, here is the question i posted before about my problem:

so basically ive had an itchy bum hole/crack for the past 5 days now. its just so fricking annoying! i had two exams today and my bum was doing my head in. i just dont know what it is. im praying for it to stop this is how annoying it is. sometimes it will itch randomly sometimes it will go. the skin on the upper crack is like irritated, and i try scratching it and it eases the pain, it feels so good but when i do scratch it just encourages the hole to itch. i've tried baby talcum powder, it doesnt seem to help.

i think im washing it alright, i use water (not soap i heard it irritates it even more) and soft toilet paper. this is embarrasing but when i fart it seems to soothe the itching (sorry for that but i thought it would help if i added detail). i admit my poo is sort of hard coming out but its not like rock, it doesnt hurt or anything its just that it could be softer, and it does scrape the sides (once again sorry for the detail) coming out.

im to scared to ask my parents, im not going to go to my doctor because i need my parents permission. i wear underwear at night. some people tell me to put lotion on it, im not too sure about this because i also read that not to keep the area wet warm and damp. i have a lot of hair down there, and i cut those five days ago (again refer to the question i posted above for more detail) but the hair i cut then was like leading from the ball sack to the beggining of the hole. it had nothing to do with the crack. it seems the itching has spread. is it something to do with the way i am sitting? eating? cleaning?

please guys this is a serious question and yes i am aware that there will be some retards saying "HAHAHAHA U GOT AN ITCHY BUM" but i dont care. i just need advice for this. this is really really annoying. i feel like crying i get so stressed when it itches. i change my underwear every 2 days (but i wear different pairs for night and day). sorry for such a long question. by the way i am 14 and have had constapation before.