Call the surgeon or talk to whomever is covering call for him by just calling his office number and leaving a message, explaining you just had surgery and are having symptoms of bleeding and possible infection. It is their job to call you and see you promptly to see what's going on. Treated early, an infection can be cured in most cases, but left untreated it can have terrible consequences; even death. It's not your job to know if it is or isn't an infection, but it is your job to notify them promptly of symptoms that concern you like this. So call! And don't feel guilty. They signed up for this.
I would call the doctor that did the surgery or your GYN. Do you have a fever?