Hi Mike,
If it helps, did you feel a slight clicking as you wound towards the end? If so, then you know you've wound it maximally cos you've reached the overwind protection thingy (sorry if I'm not using the right terms - if someone can correct me that would help).
It does sound like your watch should be fully wound. The halving of the PR makes me wonder if you had the
same problem as I did last year with the 8500 barrel. It also happened at about 2 years to my Aqua Terra. Swatch Singapore
fixed the problem swiftly and efficiently though, kudos to them. So yep, bring it back to Omega since it's still under warranty.