Well now, interesting symptom. It's rather fascinating just how
varied symptoms in general are, though they generally come down either to either quite well-known conditions or else are quite unaccountable but sort themselves out harmlessly in the fullness of time.
Note that one of our recommended assessments where the foreskin simply cannot be retracted is the "balloon test" in which you hold the foreskin opening shut and inflate your foreskin with pee as far as you comfortably can (at which point you have to cease peeing to examine the result, or let some "overflow"). If the resulting "balloon" is clearly and uniformly separate from the glans, then you are OK. If there is significant "dimpling" where the frænulum is, or you reproduce the pain in that spot, you may have a problem with it.
By remote control, it is
rather difficult to determine the actual problem. The fact that it settles in an hour or so (and is not provoked by peeing) would suggest no actual injury or damage (breakage) to the skin and does suggest that pressure is being applied to this point, and presumably you have considered the position(s) in which you lie and anything you might be wearing. You sort of imply that this is not connected to sexual activity - I gather?
And of course, the "pressure" could
be from erections if your frænulum is actually tight. I trust you have been performing the "frænulum stretch" as a major part of your stretching? If the frænulum were the problem, this would presumably reproduce the discomfort (but the appropriate response would be to continue the gentle stretching over days or weeks with the expectation that as it stretched, the discomfort would settle).
The answers to your last questions are: How long stretching takes depends a lot on how often you do it, how firmly, and for how long on each occasion. You should therefore do them as often as possible; what you are doing now sounds a good start. I suspect
that granted that you stretch for minutes at a time, stretching shorter times more often is probably
most effective for the same total time. On the other hand as you will note, we are most impressed with the concept of a device (such as the GFS
) to stretch all
the time, or a substantial part of the day.
Now, do nocturnal erections make phimosis worse? Well, if we look at growth during childhood and adolescence, it seems to me that there is a "toggle" situation. If (when) at some stage, erections manage to impact the glans (penis head) into
the foreskin opening, then they will tend to stretch it open
so that it then retracts. Whilever however, erections do not
manage to "wedge" into that opening, then the foreskin will be caused to elongate
to accommodate them. It is perhaps for this reason that external "guidance" (by which I mean, by hand) to deliberately retract the foreskin in childhood would appear to be important.
And you might care to contribute to the recent matter brought into discussion, as to what form of masturbation you are accustomed, which might not have (over 13 or 14 years?) encouraged retraction?