That is an impressive start. I would be chuffed with that. My first club 10 TT was higher than that but made good progress after that. Just keep it up and try and improve on your next effort, even if it is 10 seconds. Learn from your mistakes of the previous race. I would use a cadence level of no more than 90 or choose an average speed within your limit I.e 23mph. Eat correctly and learn from
Others. Good luck.