been practicing some classical songs for a college test, for like 5 hours
i put the guitar down and stand up and my back hurts real bad ¬¬

ive been playing electric for 5 years and never had any problems, 6 months of classical acoustic and i get this pain, any websites with pics that could show me what im doing wrong ? or some tips would be nice too =)
i got tired of my signature and i no longer has one

if u play sitting down ur hunchinmg over the top of the body and making ur sbody arch u need to sit up st8 and relax
playing for 5 hours is really long.. and being stuck in that position for that time would really give u some back ailments.. try to stand up and stretch after every hour so your muscles don't get stuck.. it's effective..