Advice needed /odd behaviour

Hi , Just found this site and am hoping someone can give me some advice.

So a week ago my Cat went missing, i searched everywehre but couldnt find her, eventually 12 hours later i found her on the roof with her front leg through her Collar, it was a really hot day and i was worried about heat stroke, she couldnt get down due to her leg being through the collar. I got her down and she drank a little water and a tiny bit of food. i thought she was limping a tiny bit but wasnt sure...the next day she seemed ok but a couple days later she started visibly limping so i took her to the vets where they said she had a fever and kept her in for a few days. Yesterday they said the fever was down but she couldnt come home until she would eat so i went to the vet where she had a huge assortment of food but she wasnt interested, i think to be honest she was pining because as soon as she saw me she ate from my hand. WE were allowed to bring her home but the vet said to make sure she urinates and deficates. 

So this morning when she woke up she came to the kitchen meowing but didnt want to eat and then she went to the bedroom acting 'wierd' she was walking with her rear legs apart as if she was giving birth and when she got in the room she laid down and put her bottom in the air, it was very scary, i thought brain damage or somehting. 

she has eaten a lot of chicken and is drinking plenty of water but her behaviour is off, she keeps wanting to be in dark places, found her behind the washing machine , then in the wardrobe, it is as if she is looking for somewhere to have kittens...she has been neutered. 

Sorry for the long erratic post , i've probably confused you all. But i am guessing there are plenty of you on here who have lots of words of wisdom.

If anyone has any advice or tips as to what it could be, could it be a phantom prgnancy?  or is it from being on the roof last week? 

Thanks in advance 

Get a breakaway collar, so this could never happen again

I've never had a pregnant cat, so don't know how they act, but apparently you have, @mich834. since you say she's acting like she is getting ready to give birth.  Has she ever actually given birth?  How long ago was she spade?  I suppose she could be going thru a phantom pregnancy., because honestly I don't see how this could be related to being on the roof, unless she did suffer some sort of heat stroke up there.  What did the Vet say about that...the heat stoke part?

If she's not spayed, she could be in heat.  She needs to be spayed immediately. 

Have taken it off of her now. Thanks

She was speyed a couple of months ago and it seemed to take her a long time to get over it.  The main reason i took her to the vet waas for her leg/paw as it got worse. He said as far as heatstroke went she was ok after they got her temp down and gave her IV fluids. But they were concerned she wasnt eating. 

She has never had kittens so i am really baffled as to her odd behaviour yesterday.

Thanks for your replies. 

Oh i also forgot to mention in my last post , that our Male cat who was also speyed a couple of months ago, yesterday tried to mate with her, he has never ever done that before, he usually just chases her around, they arent really friends but put up with eachtoher, but yesterday he pinned her down and was on top of her. I read that if a neutered male get a neutered female and mate it can produced a phantom pregnany but is extremely rare, but yesterday was the first tim ehe has ever done such a thing. 

I think you  need to get her in and make sure they did her spay correctly.  Doesn't sound like it to me, and it does happen sometimes