Is something wrong with me?

i have always considered myself as straight..and will always...but right now i am going through a very bad phase of life....i have no interest in girls...but i remember some months ago i masturbated to female nudity..(i deliberately did not go to the site but i just came accross) i am 19 yrs old...i dont have any liking for the women folk in that way..i am completely into men...i mean guys run on my mind for 24x7... i never choose to think abt women...all girls i know i just have a sisterly feeling for them and nothing else...even the thought of doing things with women depresses me...to an extent where i had to approach a psychiatrist and i am alive on medicines..i have no bi-fantasies...or any urges to go forward and do something like that...i feel so guilty for enjoying that nudity (it was not the women who excited me it was just the nudity part..the main sexual organ which i was curious to see)...now i am 19 yrs old and i feel like a mature person....i take it as if god made me realise that my way is straight and i need to neglect if any such thought comes to your mind....my guilt is still there in me...i tried explaining to psychiatrist but they just try making money...i am not poor but belong to a middle class family...Now i feel like a mature girl and wont even give a little damn to any female nudity i feel... my mother and sister explained me that this is the age problem...as you get older like 21-22 you will become more mature and your interest will change ur behaviour will change and you will let these thoughts not even enter your mind....my mom said that if you were really a bisexual then you would have never cried that a guy would never accept me n for such reasons..she said if i had been a bisexual then i would have wanted to be with women and enjoy..and would have kept this hidden....what do you guys think abt my situation?? does that happen with straight people?? i have that place in heart only for men which can never ever change...and the idea of seeing a woman that way seems a irritating idea to me and i fall in depression and cry on my bed for long hours...what do you guys think? am i completely straight?