Can you get high off of caffine
No. If you have too much, you'll start to get jittery. Have some more, and your heart will start racing. If you continue to ingest, you'll pass out or die, but you won't ever get high.
get high in what sense? caffiene is a drug in that it is a mind altering substance (speeds you up) but it does not provide any euphoria (like most illegal drugs do).