Jesus Eunos Vega

Driving on my way to work on morning I decided to down shift from 5th to 4th on the freeway. Didn't really go all out but as soon as my motor hit 4k rpm it gave a jerk and I instantly put it in neutral, as soon as I did the car died. So I pulled over and checked the oil. The dipstick was dry. So towed my car home and started fiddling with it, added oil, motor turns over easy by hand. And starts right up as long as I have my foot on the throttle. I haven't tested compression but it sounds loud and even pattern. The car also sounds like a lawn mower, and had weak power, can't even spool the turbo. Other than that the motor doesn't make any odd noises. How do I know if I truly killed my engine. Spark is good, fuel is good. Anything els I should check?