Truck sounds shitty all of a sudden...

so i get in my truck today, just had service about a week ago, and it starts right up but i start driving and it sounds like a 2 stroke motorcycle bogging really badly. I usually drive around in D but it was missing gears and was way to high. It was staying under 2000 RPMs.. i put it into "4" and it went up to about 2000 and a little higher but it wasn't sounding good. any suggestions on the problems?
i have a K&N intake and thats the only thing i can thing that is causing it. maybe its loose im not sure. Any ideas???

 

nope just got service the other day.. not on anymore but it was