hi i really hope someone can help me

i always have a uncomfortable feeling on my right side which goes round from my back to my belly button and can sometimes be felt in the left. it can also flare up and become very painful. also i go through phases of needing the loo alot and am really loose (could be diorrea) for several days and then several where i hardly go at all. just recently i have completely lost my appetite and eating can make me feel really sick (i sometimes am) and am very tired no matter how much sleep i get.

it has been like this for about 4 years now and a year ago i went to the doctor who said it was a kidney infection and gave me antibiotics but they did not do anything and i was too scared to say this because she said would have to go to hospital if the antibiotics didnt work.

although i am 18 my mum is still very protective (i am disabled - in a wheelchair due to a bone problem - bt dont believe it is anything to do with this) and comes to the doctors with me - this is why i have not been

now it has got worse again i do not know what to do because although my mum says i can go to the docs i know my mum does not believe me (as i didnt tell her everything in the past year).
also i do not like the doctors and after looking at others on the web who have not found any answers i am worried this will be the same for me and no one will believe me. what do i do please help