98 Ranger idle problem

i have a 98 ranger 2.5 with 5 speed. i just changed the oil to synthetic yesturday and i put in gumout fuel system cleaner in then filled the tank up with premiem (93) gas. now this morning when i drove it i noticed when i was changing gears the idle stayed the same. then the rpm's got stuck at 2000 when i was rolling to a stop then went to normal at a stop. now after i let it sit all day i tryed to go drive it tonight and it did not idle, it just stalled. it has no pickup if i am at 2000 or less rpm's. when i slow down with the clutch in it stays at like 3500 rpm's untill i come to a complete stop. please help me if u have any ideas at all. this is my only ride to school and work.thanks
Andrew

this is andrew, i fixed the whole problem, it was the throttle control senser.