weird dog behavior

Ok so my female had an FHO surgery years ago, so i guess from constant yrs of favoring one leg, she eventually tore her ACL. I posted questions about this not too long ago. She seemed to have recovere 100% until yesterday, I came home and she was using the leg very gently. So Im guessing she injured it again and have decided to go ahead and move forward with the acl surgery my vet recommended. but my question is this, since she hurt her leg the other day, she has been displaying weird behavior, I was thinking it was from her leg being sore but today was outright weird. yesteday and today, she will just sit there and stare, and not move, sometimes stare at me, or my wife, or the wall. Her bed is on the ground next to my wifes side of the bed, she told me that she (the dog) sat and stared at her (my wife) all night long. and just a minute ago, i got out of the shower, and my dog was sitting underneath my computer table staring straight at the wall. I thought it was really weird, why would an animal go crawl under a table and stare at the wall. now im not comparing my dog to a child but take a look at this picture, cause its exactly what she did, but under a computer table. Im thinking weird behavior caused by the pain of her leg? Im taking her into the vet tomorrow to have the leg repaired. but if anyone knows anything about weird behavior like this that would be great. the dog is 5 yrs old. http://worldradio.ch/wrs/bm~pix/timeout_kenwilcox~s600x600.jpg

[quote1306292867=Crnosrce1] The problem with ACL repairs, is youre almost guarunteed the other is gonna blow out too. [/quote1306292867] well she had an FHO surgery on her right rear leg, so that forced her to compensate with her left, after yrs of favoring her left leg, the acl has torn. so now she has had an acl on the left rear, and an fho on right rear. from now on she will be inside only. she will be able to walk, and play lightly, or go for light walks on leash but thats it. picking her up from vet tomorrow. surgery has been done.