What do you find interesting about trading stocks and web systems? Is it the challenge of getting the system to work (for that matter, have you actually written any systems?), wanting to know the thrill of what stock trading could be like, the complexity and politics, the ---? Whatever it is, have a look for it and see why you don't feel you could be trading stocks for a living (it doesn't have to be all your life, but just for now, maybe the next 5-10 years).
As several others have said, change courses rather than dropping out completely. And I realise I'm in a different country and a different system, but why the hell are you paying that much? Is that a top-notch university or something? Move to a TAFE or a smaller college or something if that cost is the only thing that's bothering you. Apply for scholarships (not sure how doable this is over there). Get a part time job to do with your passions -- anything! But don't just drop out and think 'yeah, I'll just do the stuff I like at home instead'. Come up with a plan or a goal or something, something that is likely to lead onto a paying future.
And if you like web systems so much, work on them at home while you're doing your degree!
Wolverine |