My roommate is annoying the living crap out of me, Am I being stupid about this?

Asked by L1952 (206) September 18th, 2014 from iPhone

She’s like 6 years younger then I am, I just feel like I am living with a younger sibling at times. The things that annoy me are stupid but I obviously have a roommate to help out with the bills, she pays $400 a month, This will be her first full month here and I really feel my electric and water are going to be way high . When I leave the house I leave the air on 79 because I don’t want it running all day, when I get home she has it on 77 which is crazy to me because the house is small and 77 will literally run for hours, she washes clothes like 3 times a week, she’s one person, I don’t know why but I think that’s too much, she leaves lights on, she takes 15 minute long showers and then leaves my tub disgusting! Full of hair and residue from whatever products she uses, I always go in after she gets out to clean the shower, On top of it she gets water all over the floor and doesn’t clean it up! I don’t know if I’m just being anal and OCD or if I have a right to feel the way I do? Should I say something to her? Thanks !