What Causes Frequent Urination At Night?

Hi, I am a 64 years old male, pass few days I am experience I need to go urine very often, especially first half of the night, I have to go washroom twice and once in the early morning. I drinking plenty of water water during the day due to I am taking an antibiotic pills ( amoxicillin ), I had a stomach flu for two weeks and that is getting better. I tried not to drink water after 8 p.m., only a small amount just to swallow medicine. There is no blood and burning feeling when I urinating, color of my urine sometimes is clear or light gold. Urine flows normally and freely, and bladder feel no pressure after. Am I having a kidney infection, UTI or prostate enlargement? Is there any medication for my symptoms. What else I can do now . Thank you very much.