Do you have recourse (can you go after the sellers) in regard to the house being left in a messy condition after you closed on it?
No...you don't.....not in my opinion.
Even though your walk thru was only 15 min., that was enough time to notice the state of things.
Curious why didn't you bring this up at the closing?....... or with your agent?
Also curious why you only scheduled 15 min for this important part of the process?
But.................In any event, "messy" can be cleaned up.
Very often buyers can be shocked at the walk thru once the house is vacant...it often doesn't "look as good" as it did when furnished.
I always try to prepare my buyers for this.
Once the furniture is removed, you can see indentations on the carpet where the furniture was placed, or scratch marks on the walls........or walls look faded where paintings once hung, etc.
(it's like looking at someone without their clothes (ha)......you can see all the lumps and bumps and flaws.) Same thing often happens when a house is vacated, especially if not left in the most pristine condition.
What I think your real issue is, however..............is a case of buyer's remorse.
This is a common occurrence.....many buyers second guess themselves and their purchase after the fact, and think they made a bad choice and a huge mistake!
I even wrote a blog on this some years ago, and continue to get occasional comments from buyers stating they are going through that self-doubt and remorse.
Should you put it back on the market you ask??
No, absolutely not.
Give it some time......get settled in.........put personal touches on it, and eventually it will begin to feel like home.
It's all new and you're overwhelmed.
Maybe you didn't get off to the best start due to the messy condition, but once you get organized..........and .comfortable with your new surroundings, I am sure things will be fine.