well, I go with shaky....
For me, it usually needs about a rack or two straightpool/8-Ball to find my stroke at the beginning, but well loosing it goes so fast...
On one of our first league matches this year, I started warming up and broke and ran 3 (!) racks of 8-ball then...
When the match started, I lost the lag, he broke and failed position to the 8, then I ran out and broke and ran the next and everything was perfect...
then I broke and ran to the last before the 8, and managed to miscue...
He ran out and after that I did not find any confidence... I lost 5:2, with several chances, but always misaligned positions or missed easy shots...
all concentration was f..ed up... this happens all the time, but it becomes better, the better my play gets at least...