Your concern is fair, but do not panic. Modern cell-culture anti-rabies vaccines are quite stable - once reconstituted they are meant to be used within about 6-8 hours, and short periods at room temperature do not automatically make them useless. Sitting mixed on a table for around 3 hours in an air-conditioned or ordinary indoor room usually still counts as a valid dose. What matters more is that you completed the doses on the correct days.
Next Steps
Do not restart the schedule on your own. Complete the remaining doses on day 14 (and day 28 if the 5-dose schedule is being used) as planned. If you are still uneasy about that one dose, the clean option is a single extra booster dose from a centre with a proper cold chain, or an anti-rabies antibody titre test after the course - a titre above the protective level settles the question. A pet cat's superficial scratch with no bleeding is low risk anyway. Ping me on Practo for a consult if you want me to look at your dose dates and decide on the booster.