I need some advice on my cat. [View all]

Last night we discovered that my 15 year old cat had an open wound on her shoulder. We thought it might be an animal bite (she an outside cat, a rescue) but it also looks like it may be a cyst that broke. It doesn't seem to be bleeding. The cat is cleaning it and doesn't seem to be in any pain.

She was in and out of bed with me last night and was purring. We can't find her today. We have been careful about doors so I don't think she got out. We have checked all over the house and can't find her. The plan was to take her to the vet first thing tomorrow morning.

It is not unusual for her to retreat to the basement when people are here besides me, and my son and 8 year old granddaughter were here yesterday and last night, so I'm not surprised that she hid, but she should be back in circulation by now since they have left.

Any thoughts?