Treadmill 5K

I decided to run on the treadmill tonight because I worked late and did not bring my GPS watch with me. I went to a gym that is along my commute home but had to use the restroom first. When I got on the treadmill I decided to just go a long as I felt and wanted to do atleast 4 miles since I just signed up for a 10mi trail run on December 10th. I started off at 6.5 mph and felt good so I added 0.1 to my speed every quater mile. When I got about 25 minutes in the sudden urge to go back to the restroom hit so I sped up even more to make it to 3.1 miles finishing in 27:26. When nature calls you have to answer :(. Sorry if TMI.