pain isnt normal. there is some thing wrong with your machinic in playing.

first do you have a strap?? second where is is set? looking cool by having you guitar swung very low is a lot lees important than having it in the right place to learn. are you bending your wrist?? you left wrist (or the fret hand) should be straight as possible. if your bending it too much it will hurt. if you sit down while you practice you still need a strap. that way the lower bout of the body can go between your legs and the neck will be at a higher angle to make playing easier.

of couse the instructors here can give you better advice and tutroials than i can but just relax and take your time in learning things the right way.