don't worry about it. you're at pre algebra, get through that first.

if you decided to major in math, i would think you have some ability. if you work at it, you should get it. calculus can be hard, but its fun. if you're like the average math major, chances are you will enjoy it.

just take it one day at a time, and you will be fine. if you are really worried, you can spend some time and go ahead of your class to see what to expect