Go through these in order and stop at the first one that applies. If you are reading this for someone else, answer for them.
Call emergency services if you become confused, faint, are difficult to wake, or develop rapid, deep breathing.
These symptoms can occur with a severe blood sugar or fluid-balance problem and require immediate care.
Seek same-day medical advice if the change is sudden and you also have vomiting, marked weakness, significant dizziness, difficulty keeping fluids down, or signs of dehydration.
Prompt assessment is also appropriate during pregnancy or if you take medicines that affect blood sugar, fluid balance, or kidney function.
Children with new excessive urination, intense thirst, new bed-wetting, weight loss, vomiting, or unusual sleepiness need prompt medical assessment.
Arrange a routine appointment if excessive urination lasts more than several days, keeps returning, wakes you repeatedly, or has no clear explanation.
You should also make an appointment if it comes with persistent thirst, weight loss, tiredness, blurred vision, or recurrent infections.
Every sign above is quoted from the sofidex article on Urination - excessive amount. If you are not sure, err upward — it is always reasonable to be checked.