loss of power. possible misfiring after tune up.?

My car is a 2002 Nissan quest 142k miles on it. I just had the cap,wires, rotor, plugs and gas filter changed yesterday 7-11. Today my car was doing a slight Buck when foot was on brake at a stop sign. Sorta like the engine was slightly rocking the car. When I hut the gas it feels as if the timing is of because my car doesn't respond when flooring it like it should. It'll go then jump into gear after a few secs. I'm not sure but I think my engine Therm needle may have went a little over the middle point.it may be me just seeing things tho cause I have good pressure on both hoses both were hot. I'm taking it back to my mechanic especially sense I got a solid check engine light. Btw there are no fumes, leaks or smoke and the above started day after tune up and some mild driving.