Hi again, Lori.
I was hoping to hear back from you with some additional information, but, I will send an answer now, and if you have any further questions, just click 'Reply.'
I asked about medications Lucky received, because if he was sedated while at the vet's because he was so upset and aggressive, they most likely kept him sedated for the duration of his stay, so he wouldn't pull out the catheter and the medication not completely out of his system, yet. In addition, he was probably given pain medication which can make him feel pretty zoned out, and he might have also received antibiotics, which can also cause lethargy.
The fact that he's laying in his litterbox can have several causes: he may feel like he has to urinate, but right now, his bladder and urethra are so irritated and probably inflamed, that he's uncomfortable, but keeps feeling like he has to go, but he really doesn't. In addition, if he should be running a low-grade fever from a possible infection, he would seek out a cool place to lay and the litter feels cool to him. For sanitary reasons, I would remove him gently from the litterbox and place him on a towel near the litterbox, in case he has to go again.
The fact that he did urinate a little bit is encouraging and his urinary system just has to return to normal after this trauma.
Try offering him water and an ice cube to lick; if he should feel nauseated from the medications, licking the ice cube will help. Continue to monitor him and when he seems a little more alert, offer him a small amount of the prescription canned food. If he's not interested, try offering small bits from your finger and/or your palm.
He does need to rest and his body needs to heal from what he's gone through, plus the medications need to leave his system. Hopefully, he will start feeling better, as the days wear on, but if he still won't drink, eat and does not urinate again, by tomorrow, call your vet to report this and discuss options.
I hope Lucky will start feeling back to himself, very soon!
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