Its all very well to have a career to fall back on but a degree won't necessarily get you a career several years down the line should you need to fall back on it. After graduating you're expected to accumulate experience. Think about it like this: who might employ an unemployed former pilot who just happens to have a degree in chemistry?
Our former Director of Personnel had a degree in chemistry but went into public administration and got into the airline business by accident. One of the general management trainees in our graduate trainee scheme started at uni doing media studies, then switched to hotel management. She didn't get selected for what she studied but how she performed. In my own case, I'm a reformed Licensed Aircraft Maintenance Engineer with a degree in accounting & finance of all things. Aeroplanes are much more fun than banks, I might add...
If you want to be a pilot, be a pilot. Check that you can pass the medical as Ghengis suggested, then throw everything body and soul into what you really want to do. If it all turns bad, you can do the degree later.