Emission Control Malfunction & Driving problem

What is your question?

I had my car serviced for an oil leak 3 days ago and my oil filter housing adapter gasket was replaced. It fixed the leak and drove fine for 3 days. I started it this morning and the Emission control light was on. I attempted to drive it but it has no power and has difficulty changing gears so something is clearly wrong. Could this be related to the oil leak repair? What kind of malfunction could have caused this out of the blue? No prior symptoms? Thank you.