I have had a rhythmic tingling in my right heel for 2 days now. I don't notice it as much when I'm walking around but notice it when resting/sitting?

You've got Rhythm. I would say the rhythmic pattern is caused by the hearts beating rhythm. The fact that you feel it's rhythm means that the heel is likely inflamed. The inflammation causes congestion and pressure on the nerves which makes the tingle. Elevate your feet, higher than your heart, if you can. You might need some better foot wear to take some shock off your heel.
Likely not serious. Don't know what this is, but you only notice it when you are not doing anything else to distract you. Make sure you aren't wearing new tight shoes or having any weakness in the leg or foot and then try not to worry about it. It will most likely go away.