It's getting harder and harder to look at pix of LiLo these days... girl is aging WAY too fast! Stay in one night, Linds, and get some much-needed sleep.

La Lohan is back in LA after her New York trip - she went to Boa Saturday night with sister Ali and company. At 12:30 a.m., she dropped Ali off and stopped by the Sunset Marquis for a little under an hour. Then she ventured to Largo in WeHo at 1:30 before leaving at 2:15.

Uh, what's with all the late-night hopping around? That's never a good sign!