i was on the highway and the car start shuttering and now every time i press the gas pedel the car vibrates and feels lack of power!

Whats my problem?

 

Misfiring on one or more cylinders. Use the search feature for "misfire" and you'll find threads describing how to diagnose where the misfire is occurring. Or you can scan your car with a VagCom or other scan tool and get the codes that'll point out which cylinder(s) are at the root of the problem.

 

You should not drive with a flashing CEL. You might burn
the CAT.

 

i've been there, we've all been..

When you misfire, one of your coils are probaly gone, Do not replace 1 of them, Do them all, or you'll be back checking codes on the next one that goes bad.

Change all 4 coils..Change all 4 spark plugs.. and make sure the wiring is good.
they work hand and hand.
its like a 20 minute job, pretty simple but really the only way to fix it.

 

Def sounds like a coil pack, just happened to me. Had a spare in the trunk, a common issue i found out. Call your local audi dealer there is a recall currently, scheduled. Mine for this week. Good luck.