Is it too soon to change companies? Please advise.

I have been out of school for 5 years and have jumped from job to job every year. Each time taking a huge pay increase!

I am currently at a position where things change everyday. I was recently given someone elses job as well (tech writer) but with a modest 5k pay increase. I asked for more but was told that they could not justify what I wanted. I currently make 75 with the raise.

The day I was given my raise I was contacted by another company. They want me to be just a trainer, and for more money 85k. I have only been at my current employer for 6 months. Is it too soon to change jobs?

What would you do?