I don't think staying up late is part of the problem unless you are saying your sleep is already disrupted.
I knew someone who dreamed she was in the bathroom but she was still in bed. She had had a lot to drink that night so probably wasn't waking up normally (not to mention that alcohol dehydrates), but your problem is occurring more than once.
I'd look at whether you are drinking anything that causes you to eliminate a lot of urine or otherwise irritate the bladder (e.g. caffeine, some artificial sweeteners). I'd look at whether you have any UTIs or bladder infections that could cause an intense need to urinate, that might now allow you to wake up enough. I'd also look at any sleep issues - are you having additional vivid dreams, are you waking up refreshed or exhausted, etc.? If you're not waking up thoroughly, you may have the vague "full bladder" feeling but are not coming into full enough consciousness to actually get up.
I don't think "getting old" is a good answer for this! Something is off. Could be something to talk to your doctor about, but that could involve urodynamic studies (bladder capacity) or sleep studies (learning more about your REM sleep and dream cycles). There are medications that help with bladder issues (antispasmodics, for example, but they can cause dry mouth which makes you want to drink more, creating a vicious cycle in some people.
There are also nutritional ways to address improved cellular health, which can help with bladder muscle problems and frequent UTIs (even low grade ones) and also sleep problems along with organ repair (which occurs during sleep). I do a lot of work in this area and have seen a lot of improvement in people's lives with the added boost of improved immunity and all kinds of body functions.