This most likely sounds like an over active bladder. Although urinary infection cannot be ruled out without doing an urine test.
This condition can be due to stress, obesity & sometimes without any reason. Avoid tea, coffee, spices. Do pelvic floor
exercises(Kegel's) which will help you hold the urine for more time.Weight loss
has shown to be very effective in this condition.Avoid water and fluids in the evening hours which you are already doing.
There are drugs to treat if this is causing too much trouble. Most commonly Oxybutynin
are prescribed for this condition.
So first get an urine test and if there is no evidence of infection, you can try these measures and if required medications too.
I hope this answers your query.