I take it that you are starting with your degree. If so, it doesn't surprise me that you have doubts about whether you made the right choice. Consider that the first years of a science degree are usually quite general in their contents and scope, so you have to swallow a lot of crap you may not particularly enjoy. Man, I hated chemistry with all my soul (I'm a chemist). The first degree may very well be a steaming pile until perhaps the final project. If you like research, the fun definitely starts after your degree. It basically has absolutely nothing to do with the undergraduate experience, and it really is good fun.
If, on the other hand, you don't plan to keep on studying for the rest of your life, you want to get informed about what the jobs are like out there in your field, and imagine whether you have the guts to endure 40 years (and counting) of it : D
You don't really need to take another degree in computer science in addition to your 'real' science degree. If, as you said, you are the geek kind of guy, you can learn what you need without having to go through the formal process of getting the recognised qualifications--and enjoying it without any pressure. Others may comment about how awesome a CS degree is, and they will be right for it is entirely subjective. To me--and perhaps also to you since you chose biotech--computers are a tool to do the cool stuff; on their own they are grey and boring things. Means without end, if you want. But hey, I heard some people write device drivers as a hobby...
PS. I noticed you are interested in putting some distance between you and the evil forces out there. If a Kalashnikov is not made for you, I suggest research again. One of the few jobs you can have without having to hide from your own face in the mirror ; )