This is not an SQL Server only issue, I find it to be true in most computer work. I must find the answers and solve the problems. It is me against the situation in a cage match. 
Sometimes I win, sometimes I resign and come back after a day or two and win. 
The important thing to remember is your time awake and working affects your ability to think straight.  You can become snow-blind (if you will) and the best case scenario is you don’t do any damage.
You need sleep to be your best, look at all the studies that show overworked people are not just less productive but actually make more mistakes.
Even knowing this I too, will often think I can fix it just give me five more minutes.
I call it the Video Game “Level Up Syndrome”