It looks excessively dry, but no comment other than that.

i gave it 2 gallons of water just yesterday

Look at the soil, it looks totally bone dry. I suspect you should give it like 20-50 gallons of water (slowly), like drip from hose, if you haven't had at least an inch or two of rain in the last week.

There is not enough information in your posting.

Where are you located? (We have half the country burning up in drought and the other half is flooding...., Assuming you are in the USA.)

Show a pic of the rest of the tree. You do realize that Crape Myrtles are very naturally exfoliating (shed their bark).

Flaking bark is a normal feature of this tree and part of its appeal. I'm much more concerned about how each of the 3 trunks appears to have its own separate root crown, as though the specimen consists of 3 different cuttings stuck closely together in the same pot. To produce a fuller looking product at the sales yard.

really? you think they did that?

I wouldn't put it past an enterprising money grubber to have done three cuttings.

"i gave it 2 gallons of water just yesterday"

If by "newly planted" you mean that you installed this plant smack dab in the middle of the summer then it needs a whole lot more water than that. Like dbaron said, a hose on a slow trickle is necessary, and move it a time or two to ensure that you hit the entire root mass.

Can you guys expand more on the subject of 3 different cuttings? How big of a problem is this? Is there a way to confirm?

Well, umm, no easy way but to dig a little in the rootball and see if it comes to a single stem. And the consequences are that eventually all die but one stem (out competed)...though since crepe myrtle naturally sucker (most), it'll have multiple stems by then.

Just a cheap shoddy practice really, not great harm.