My range is getting higher, and after a great weekend practicing i noticed i can hit higher notes and hold them pretty much as long as i want now! Im only playing c,d,e,f,g on top of the staff because that my area im working on, but its a good improvement for me to be able to hit and a g, and have it sound nice and controlled... anyway... I noticed the next day my abdominal muscles are hurting like i had been doing press ups. mostly the outer ones like the obliques. Is this a cause for joy as in a "no pain no gain" scenareo or something else i'm doing wrong? thanks.