01 F150 Supercrew Trans. Out

Took Off At A Stop Today Heard A Clang Then Went Into Neutral. Checked My Shifter Was Still In Drive But Got A Little Pull Out Of Trans To Get Off Road. Stopped Looked Under Over Etc Got In Put In Drive Away I Went. Tickled It Was Over But When I Reached 20 Mph Went Into Neutral Again Pushed Overdrive Button Off Drove Home Then But Slow. Have No Reverse At All And Drives With Od Off But Wont Shift Till About 3500 Rpms. Anybody Got Ideas Im Sure This Will Be Costly Thanx Dave