Cat incision infected?

My kitten female was fixed at 8 weeks old and it looks like her incision is kinda swollen like the picture that I seen on your site please I'm worried I rescued her they fixed her they chipped her already I'm scared and I'm worried its swollen red I can't tell if I have fever it looks like the young kitten the name starts with S on your site should I keep her locked up in a kennel or let her keep playing like she's doing and she just started throwing up 3 days ago throwing up she eat throwing up she eat throwing up she eat there is no discharge but I don't know how I mean I can't tell if she has fever or not in it she won't let me get close enough to feel it because she is so hyper she thrown up about 5 times maybe 6 n 3 days please help please this kitten is for my autistic boy I don't want her to die I don't know what to do I don't have the money to go to the vet

Did you adopt her from a rescue? If so, call them and ask about follow up vet care with their vet. It does sound like she needs to see the vet.

I wouldn't think she needs to be in the kennel unless she is so active that she is risking opening up the incision. When my cat was spayed, that wasn't necessary.