Pulled the trigger too early?

I started an MM/Ent AE position mid August, spent two months in training in a new industry before receiving my first contacts to cold call. unfortunately I had a pre planned vacation for 1 week, which was the same week I started out of training. the following 2 months of Nov and Dec were holidays and office closures for us and the prospects. I finally closed my first deal, signed contract on Jan 11th 23 and then was let go on the same afternoon. I had another contract out and a verbal yes, just waiting for the prospect to arrive back from holiday vacation. I was informed that my performance lacked but had more activity then any other sales rep over the holiday season. I was ramping up to crush this role and show up the team that has been there for 15+ years. Was I let go too early without a proper chance or did the sales manager make a sound decision? or does it seem that I was let go suspiciously right after drumming up business? trying to move on but not sure how to present this to a new employer... 

sales cycle 30-45 day avg. 

quota 12 per quarter