I tried squatting this morning as suggested, as well as waiting a little longer on the can to see if anything came of it. I did pass more stool, each time having kind of a double-movement of my bowels separated by a few minutes. I may have even had that little squirt of pee at the end that you guys mentioned. But I still had to go again shortly after, and the overall time still wasn't all that long on the can. Like 5 or so minutes each time.
I think my colon's just like that. It may have adapted to all that I used to eat everyday (60g+ fiber, 3600-4200 calories, etc). But I do feel better off now!