Salah purity, do I have to repeat it in this specific case mentioned.

Salam dear respected brother/sister.I have two questions.Previously I had a urine problem (but now realise I needed to let drops come out for a few minutes in the toilet),and so I used to pray sitting as sujood would cause drops to come out and affect my purity during prayer.I found out later that I should have stood up and prayed ignoring the drops.Do I have to repeat these prayers and am I sinful for delaying them.My second question is that I owe 1000 pounds worth of expiation for oaths.I am 15 and so can’t access and send the money I have for a few years.Do I wait till I have access or make it up by means of fasting right now.I would ask my parents but know they wouldn’t listen.These matters are shaking my belief and so I ask that you please reply as soon as possible.Jazakallah khairun.