You're such a trouble-maker, LOL!

When I said not to keep score, I meant not to be overly critical of your performance by using all sorts of metrics, counts, and analysis. Of course you can time yourself if you like, but it doesn't have to be super accurate. Approximate distances work just fine as well. Like I mentioned earlier, I just gauged how long to run versus walk when I first started running by city blocks, which vary from place to place. Even now when I'm doing interval training (a combination of sprinting and jogging), I'll just count my steps and use that as a measure rather than having to carry or look at a watch. There are lots of options and they don't have to be perfect to work. Remember, perfection is never the goal.
Honestly, you'll probably have an easier time experimenting outside rather than on a treadmill. The reason is that outside you have instantaneous control of your speed. With a treadmill, you have to access the speed buttons and wait for the treadmill to respond. Plus, you have to know what speed to select, which is pretty difficult when you're trying to find a good pace. It's much easier to run on a treadmill AFTER you get comfortable running in general.
I was lucky that when I started running, I had someone with me that already knew all this stuff and could give me tips as I was going. You might even see if you can find a running club or someone in your gym that will help you out. It can make a huge difference.
Jamie