female cat, fixed, odd licking behavior

Question
My little cat, Sydney, recently got fixed.  She was obsessive about biting at her stitches, so the vet examined her and removed them early.  Everything seems to have healed well. Her fur is growing back too.

Since then, Sydney spends lots of time licking her teats... only the front set.  Sometimes she seems to be trying to nurse herself.  She sometimes does this when she's being petted and is purring loudly.

What is going on with her?

Answer
Jaime,
Actually, I really don't know.  It may be a security thing,  but whatever it is, I realy think it will eventually stop.  My cats will knead me and purr loudly.  I always felt that was a sign of contentment, so it may be the same type of thing.  I wouldn't worry about it unless she does it so excessively that it causes bleeding.  

God Bless,
Becky