Try not to worry about the darkness of the lines (especially on those cheapies)! They're not quantitative tests, meaning they're not made to be compared for darkness as it won't correspond with your actual hcg levels. They're only designed to give you a yes or no answer. Plus hcg levels in urine vary with all sorts of factors like the time of day and amount you've had to drink recently. If you're getting bloods done, that will give you a better indication. Either way, I'd say step away from the tests, you're only going to drive yourself crazy!