Would you be angry if?

when i was 13 i caught my big brother, who was at the time 18 spy on me while i was taking a bath, i was angry at him because to me its kinda dusturbing.. he went overseas for a while and came back, i usually wake up at 5 the morning and take a bath before school, when he came back he lived with us again, i never noticed that someone might be watching me and our doors are pretty crappy so you can see through it a little, well the one day my twin brother told me that he saw my big brother standing at the door until i'm done bathing. i found this very dusturbing because his 20, probably shagged alot of chicks before and now his spying on me.. WTF! i told my mom bout it and she said its nothing his just curious but it really bothers me, his scary seriously. Now i have this stupid phoby where i wont take a bath when people are close by. i just need to know if i'm not over reacting on this and if other people also think its a little mes'd..?