Just to double check since it's so easy to do when you have all the plugs out to begin with... .you are doing a plugs out compression test, right? - all the plugs are out so there is no restrictions (compression) in any other cylinders.
It will also expose a cross leak between cylinders (very rare) which is why it is preached as the right way to do a compression test.
If you went to the trouble of pulling all the plugs out, no reason not to spin it 5 more times and write down the numbers... trivial at that point.
Anyhow, I re-skimmed and I am with Shran on this one, post #18 - intake gasket. I think your low compression on the first test was either just OE (operator error) or gauge not perfectly sealed (the back ones are the hardest to get straight), flakey gauge, etc - not anything to worry about... my money is on the intake gasket.
If you aren't confident in your compression test or did it plugs in and just want to repeat, sure knock yourself out, but I don't expect it to be there.