New pain 8 weeks post tummy tuck. What can I do?

You should call your plastic surgeon and let them know your symptoms. Ask if there's anything you can do/take to reduce the pain. I would also suggest no exercise for now until you see your plastic surgeon. Best wishes, Dr. ALDO 

Check with your PS to be sure, but new soreness and or spasms sometimes occurs as you re-engage your core after TT.  Gentle ramping up of activity, and some naproxen, ibuprofen or tylenol help.  Your core is likely de-conditioned, and this frequently subsides with gradual reconditioning.  

Thank you for sharing your question and I am sorry to hear of your discomfort.  Hopefully all you have suffered is some mild muscle cramping and irritation which should resolve with rest.  Because this is an acute change in your recovery I would reach out to your surgeon so that they know what has taken place.  As for additional treatments I would try NSAIDs and your compression garment.  Hope this helps.

Make sure that you reach out to your surgeon.  Possibilities include:
A suture placed in the mid line that got stretchedMuscle SpasmsFocal Swelling
I am sure you may have other possibilities, but just make sure you talk with your Plastic Surgeon