Everyone pees slower at night, and immediately after waking up. When you're younger, you probably didn't notice, but if your prostate is enlarging, then it is likely to become noticeable. This is because relaxing the urinary sphincter is done by your autonomous nervous system (not under conscious control), and the part which controls this goes to sleep too, but takes longer to wake up than your conscious nervous system. So if you try to pee when you've just woken up, the part of your nervous system which relaxes your sphincter is still somewhat asleep. Many people have another pee quite soon after the first pee of the day (and there's a different reason for this), but find the second one is faster than the first one.
Hesitancy can also be psychological, e.g. peeing when someone else is present, or even just worrying you might not be able to pee might trigger it. Does taking your mind off it help, e.g. sitting on the loo and reading a book or doing social media on your phone, rather than concentrating on trying to pee?