Belt Question...

This is really stupid, but I am curious so I am going to ask. AM I the only one having trouble with new belts? I got a new alternator belt not too long ago. The old one was stretched and the alternator was against the fender well and could not tighten any further. So I got a new one about an inch shorter. Installed it, tightened it good. I noticed the last couple of times I've driven the belt squeals in brisk acceleration. So today, since I was under the hood installing my carburetor heat shield, I tightened the belt up. Is it just me or do these new belts stretch too easily? I don't remember ever having this problem before. I can put the pry bar on the alternator and just stretch it like a rubber band.

I have not had any trouble w/ belts (on cars) , if u can find a kevlar belt in the size u need , you`ll probly never have to replace it .