I feel your acne pain!!
Yes, a trip to the dermatologist can be quite spendy, and because it seems like that is not an option for you, let me give you some tips. There are many products that come in sets, other than proactive. Clean and Clear has a system, as well as Neutrogena. Make sure you get the right one for you. If you have sensitive skin, get the sensitive skin kit, because even if you have severe acne and buy the severe kit but have sensitive skin, your face will be very angry with you and will not improve. These sets run around $20 and last for about a month, which is quite reasonable compared to buying many different products. Using a system also helps to decrease irritation that may happen from using different brands together. As for the hormones, sorry. You're going to have to be patient. There's not much you can do for that except get older and grow out of the raging hormone stage. Birth control is the only thing that will truly help control hormones, which can help those plagued by hormonal acne. Because you can't go to a doctor, this is not an option either, not to mention it's always a fun conversation trying to convince parents to let a 15 year old have birth control:)
So please be patient, and if you try a system, remember that you will not see results for a long time, but stick with it because these things take time!