When i start my truck up in the morning it idles up for a about 30 seconds and then idles down but when i take off it idles back up and won't idle back down until i stop.Then when i shut it off when it is warm and start it back up it idles high again and won't idle back down until i stop.

no
timing has nothing to do with idle speed
run the fault codes and check for a faulty idle control sensor

just tune your idling a little bit

Its normal .. its the automatic choke,,, no problem,,, the high idle should last longer in the winter.. when it "cold" in Florida.. hehehe...

first, try to clean your throtle body with a good cleaner an a tooth brush, open buter fly and clean all around, front an rear, when starting it hold your gas pedal down until it starts letgo quickly but keep it running at 2500rpm until engine clears(some smoke may be heavy) this will help with idle problems and clean some carbon from valves and combustion chamber,.second your egr valve may be gettin partially stuck open, disconect hose from top of it, use a small bolt to plug vacum hose and drive it normally if problem doesnot occurs you need a new egr valve,
good luck.

Sounds like the Throttle Position sensor or the Idle Air Control Valve causing the issue

Assuming you don't have any stray vacuum lines, I'd look into the TPS (throttle position sensor) Most idling problems can be traced back to the TPS.

your iac or idle air control needs cleaning. the idle valve is probably stuck and not letting engine idle right.

This idle condition is normal for a cold start, the computer is controlling the idle for proper fuel burn. It is not necessary to wait five minutes for the idle to come down. Allow about one minute before putting into gear and driving.

I would check the intake air temperature sensor