I have been stretching twice a day for about 2 weeks now. I do three exercises twice a day, for about 7-10 minutes each. They are:

a) the frenulum stretch
b) stretching the frenar band (grabbing tip of foreskin with 2 fingers and stretching to the sides)
c) pulling back on the foreskin

I have made a lot of progress when pulling back the foreskin because I can see more of the head than I was able to 2 weeks ago.(even though it takes about a minute to expose as much as I can). So progress has been made here.

But when doing the frenar band stretch, I have made no progress whatsoever. I use a pen-cap for this exercise because my foreskin is completely shut from the tip.

I know it's way too early to expect results, but I was wondering, why did has the "pulling back foreskin stretch" made progress, but not the "frenar band" stretch?? I've been doing both of them for the same amount of time, twice a day.

Since you are doing both, it's really not possible to tell what is causing the progress. Does it matter? Keep your eye on the finish line.

OK, I detect that you are not actually getting inside the "fraenar band" - the tight part of the foreskin - with your fingers, but the "grabbing tip of foreskin with 2 fingers" is only stretching near the tight part.

The fact that you can indeed see your glans under some circumstances and that you can get a pen cap through the tight part indicates that you are getting somewhere. Read back a fair way here to find description of getting one, then more fingers actually inside the tight part of the foreskin; this is what you need to do to really "get going" on the stretching. Using your "poor old" glans as a stretching object is praiseworthy, but getting a decent size object (and your fingers are really good for this) inside will be far more effective.