Grey belly after spay

I'm not so sur how to even describe it but Sophie was spayed today and after I brought her home, I noticed that her belly is grey. And her sutures are a little buldgy. She's also acting very needy and won't stop whimpering unless she is laying in my lap.
I'm nervous as top what can be making her belly grey. It's the whole back half of her belly (including her nipples).
Please settle my mind!

It may just be the solution they scrubbed her belly with prior to spaying her.  You should call and ask your vet.  The slight bulginess of the sutures is normal, and it gets worse before it gets better because it swells some.  As long as the sutures are holding, or the surgical glue (depending on which they use), it's not unusual.  As for the clinginess, that is totally normal for males or females.  They just need to be close to you as much as possible the night after surgery and sometimes the next day.  Cuddle her up and watch tv or a movie or something.  Devote the entire night to her, she deserves it, she's had a rough day.