Hi frankr
First, relax. Your max risk is what you paid for the spread and
second, the stock is moving in your expected direction.
Third, are you still bullish? If so then hang onto your position. If not and you are now bearish, then simply close the spread (sell the calls you bought and at the same time buy back the ones you sold - if you're not sure how to do this then check with your broker - iow you need to close the trade the same way you opened,i.e. as a spread).
Ok, now, back to basics. Before you open a trade you need to have your plan - exit stops (profit as well as loss). The stops need to be a bit loose because of the slippage issue with options, but you might want to pick, say, a 50% stop loss and a 100% profit stop (this is just an example). Based on the loss stop you can work out how much of your total capital to put on this trade. For example, your money management might dictate that you only risk 2% of your bank on a single trade, and of this 2% you are willing to lose half (50%). So, for a $10000 account you would take $200 and buy your spread (e.g. each spread costs $20 so you would buy 10 and close the position if its value dropped by 50% or went up by 100%).
Now, you need to work out which spread you want to buy and for this you need to model it so you can compare the different spreads and how they will behave under different scenarios (price up/down, time decay, iv changes). As MTE mentioned, time decay is an issue and your spread won't reach max value until expiry (no time value remaining) or if there's a very big up move (which would basically have to put your spread so deep itm that virtually all time value is lost from it).
Ok, that's enough from me.
Don't despair, options are complex and take some time to work out, but you can do it if you stick with it - the hard thing (as another poster pointed out) is to maintain interest long enough for you to become proficient.
Happy trading.