#1
I changed the strings on my fender strat using the same gauge strings that I allways use (ernie ball super slinkys) but this time for some reason there's so much tention, I've had to put it in Drop C just to feel normal!!
#2
Did you stretch out the strings before you put them on? That helps them hold the right tension. Sometimes it just takes it a bit to adjust to the new strings.

Also, brande name (Ernie Ball) =\=string gauge. The gauge is the number on the package, i.e. .11-.52. I just made those numbers up, dunno if that's an actual gauge.
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