Try working through the beginners course on Jusringuitar, won't cost you a penny, unless you want to donate or buy something.
I know from my own experience, it can be very painful and frustrating at the start
Most people say it's better to practice as often as possible, even if it's only 10-15mins a day, rather than doing a few hours once a week.
Stick with it, the pain does go away once your fingers get used to it, might take a while though