i drop tune to C when i play but the neck or action or something on my (now) old guitar got so messed up that it's not even worth repairing. before i get a new one i would like to make sure what i know how to properly care for it since it appears that how i have been instructed has resulted in sad results. some of the biggest problems i have, stem from the basics

---im stringing my guitar. i use heavier gauge strings. how many times would i wind around each knob. also, how taught do i pull the string through the tuning knobs before i begin this winding process?

---when im tuning, after i have re-strung, i can hit the (let's say) G note on the second string but i can also go through the scale again and reach G again on the same string albeit the strings are obviously very tight. which is proper?

this leads to my next question...

---could i have pulverized my action from stringing too tightly. i suspect the neck is bent. i mean this action is bad the higher you go on the fretboard.

im sure this sounds bad, but i really could use the help

thanks