Sounds like maybe the truss rod is too tight and you have some back bow going on. With a capo at the first fret and the sting held down at the highest fret you should have about .010 to .015 relief at the 8th fret. Loosening the truss rod counter-clockwise will increase the relief, but you should probably only change it about an 1/8th to 1/4 turn before retuning and checking again (give it some time to settle once you make the changes.) There are tons of YouTube videos on guitar set-up on the internet, the best are from the pro's at Fender and the Stewart-MacDonald guys (Dan Erlewine and Eric Coleman). Also the Fender factory manual that comes with each new guitar has all the basics in there along with all the standard setup specs. With that being said a few specialized tools are required, like feeler gauges and a small machinists ruler (and an optivisor magnifier in my case) so you have to weigh those costs vs. paying a luthier to set it up for you. Worst case, you get into a fret leveling/re-crown which costs more (tools or $). You will know which is right for you, but it is very much the give the man a fish/teach him how to fish thing. Good luck, and even if the existing neck is bad it can easily be replaced!