Is my cats incision infected?

Since my 7 month old kitty was spayed on Saturday I have been a nervous wreck. I haven't had any experience with this type of procedure since I was a kid. I have been having trouble monitoring the incision. Everything I read says to watch out for redness and swelling. There doesn't seem to be much swelling, just a little bump around the area. However it is red. It looks like a scab. How do I determine whether this is healing normally or it is begining to get infected? She has had a little discharge but that has been minimal and the wound does not appear to be open. Am I looking for redness around the incision or on the incision itself. It just looks like a scab to me. She is very active and hasn't been acting abnormally. There was one day where she wasn't eating much a few days after the procedure but her appetitie has returned. Seperately she has had some dark brown "gook" discharge from her eyes. Pardon my expression but it looks like little  brown boogers on the area between her eye and nose. I have just been wiping them away with a damp tissue.

In short does this sound like anything I should worry about? I want to take her for a check up but really cant afford it for a few days. I certainley don't want to take her to the vet if I am just being overly paranoid. Thanks for your help.

thanks for your help

She is eating and drinking fine. I cant tell if that particular area is warmer thank the rest of her belly. She seems fine. Maybe a little sleepier than usual but it just may be that she is tired. She is definately eating. I will keep paying attention to these things. I will likely take her in for a check up some time this week. Thanks