My poor orchid

I have an orchid and one of the blooms is shriveling up and turning brown. I've only had it for a few days, I don't want it to die. I googled for some info and found this. I think I was over watering it. Maybe too much sun, or not enough, I don't know. I don't want it to die. If anyone has had an orchid and can give me some advice I would be much appreciative. Thanks.