I was brushing my teeth last night and notices that there was some blood when I spit, I rinsed well and listerined. I also use a water pik. This morning when I was brushing My gum behind my wisdom tooth was real sore, raw feeling. Could this be the beginning of an absess or should I worry about it.

Just keep it clean, probably had something lodged in there that caused the irritation.

Floss and or water pik a couple times a day, it will probably clear up, if it doesn't, you should have your dentist take a look at it.

Make sure you are using your waterpik on a lower power level and not pointing the tip into the gum. You could force a food particle or piece of tarter down into the gum which could cause an abscess. Rinse with some warm salt water for the next couple of days and leave the waterpik alone.