Start out shift problems

I have a 3.8 2000 GP GT. The trany fluid and filter were changed at 80K approx. It now has 150K on it. The car is starting to exhibit shifting problems when taking off in some cases. You can tell the rpm runs up higher than its normal shift point before it shifts. This is only between 1-2 gear all other gears shift fine. There are no indicator lights on the dash. Any ideas?

I would suggest to have the trans scanned by a dealer or a trans shop to see if any trans DTC's are stored.

could be lots of things including engine problems. Does it do it worse cold/hot?

so far it has just done it cold.