I have always had issues with my sleep schedule...in recent years though it got really erratic on me and I asked my doctor about any options I might have. he asked me a lot of questions and examined my throat (thumping the outside with flicks and opening my mouth like a bear trap and shoving a light down it). Then said that I likely have sleep apnea.
He said that tissue in my airway (which for reasons not fully understood) could be weak, and while I sleep, collapses intermittently. Which causes me to partially wake up briefly so my brain and body can deal with the issue.
The only way to actually verify this was to measure my sleep interruptions vs. what they no to be within normal perimeters, and so he ordered a sleep study. This is where they put scratchy cream in about 100 places across your entire body (most of it on your head), and this acts as adhesive for diode connected to thin wires.
You then get into bed (this is at a sleep study clinic) and go to sleep (which can take a while being covered in wires and generally being discomforted). While you sleep they monitor everything, your body temperature, brain activity, blood pressure, muscle group twitches etc. As well, there is at least one technician there not only monitoring the monitors but you, for visual confirmation of what the readings say.
I asked the technician if there was such a thing as a night person. he informed me that sleep study was not just his job but his hobby (he was studying to be neurologist or something, at that). He said that given such, he has read many different papers published by colleges doing studies that show every society (more or less) has night people.
And, furthermore that every society that has surplus living and industry requires that some people be awake at night for things to run smoothly. And, it has always been this way with human civilization. From watchmen/guards, to bartenders, to astrologers and astronomers, and even nocturnal cults or sects of religion... all these are night people.
He said from what he read a fair estimate is that under the most healthy circumstances around 10% of a population will be night people. But, the more surplus a population has and the more industrious it is with it...this percentage climbs on an escalating curve up to about 30%.
Even more then this. Night people appear to be inclined on the level of their base nature to be awake at night and adopt habits, hobbies, and careers that are best done at night. In most cases a night person can be a day person if they need to be. But, they will always want to naturally be awake at night.
So far though, Most of this (what we know about it) is through observance alone. And, the night person has yet to be verified on the medical science level.
More recently I found these short videos which has helped me keep a little bit of a better sleep schedule for my lifestyle and understand rested states a little better:
Should You Use The SNOOZE Button? - YouTube
Why Do Cats Purr? - YouTube
How to Sleep Better - YouTube
So, it may very well be that you are not night people because you play with lasers. But, instead laser people because you naturally want to be awake at night.
Please get checked out! Things have change considerably regarding healthcare recently. If possible please check your local community programs. It is a severe pain in the behind, but it does really sound like you should at least get a checkup. 
