I have a 94 toyota camry.and its picking up slowly.going to 3000 rpms.

Are you basing this on a standalone GPS unit or a phone App? They are not accurate, and out of the two, Apps are the worst..

high idle on starting is normal as it is the same as a choke being on. When it drops back it should be around 900. However tacos in cars are not real accurate under a 1000 rpms so have it checked manually with a rev counter. Run the fault codes to check for a problem.

You really need to test parts and report the tests before you change them. The readings from the OLD sensor, scanned and voltage tested (prefer both) are invaluable in evaluating a throttle sensor.
If it wont go over 3000 ever, my guess is there is a fault code somewhere or soon will be. If it runs terribly getting to 3000, but idles OK, its likely a fuel problem. Your MASS AIR FLOW SENSOR is on the other side of that rubber tube that attatches to the throttle, if the tube cracked while removing to access the TPS, it could cause that. It must be sealed tight or incorrect airflow is measured and the car only supplies enough gas to match the measured airflow past the MAF sensor.
Get a scanner, check data and codes. If you cannot...then Im afraid the hard answer is you really need to take it to someone who has one. Random guesses are never a good thing, they are at best lucky, at worst expensive and damaging. More often the 2nd than the 1st.

Possible restriction in exhaust have convertor checked for blockage

big deal

The gas could of lost some of its octane which will cause a pinging or rattling noise try oil change and fresh gas.

check the fluid level if that is good then i would say you will prob need a rebuild

1st to do,replace fuel and air filter, spark plugs.

MAF sensor.. egr valve

are there any codes?

the V6 has a rev limiter in gear that keeps it under this in first gear. put the tranny in Power mode if it's an automatic. it will **** more gas, however.