Is it fluid or true engorgement?

Finally was able to hit 30 minutes mark today. Usually I would pump up to 5 mmHg. This high pressure will cause restriction in blood supply to my glans within 10 minutes. Upon re-attempt to pump back after 5 minutes of rest, the fluid build up will be so great that I had to abandon pumping after 10 minutes.

Today, I kept pressure just a 4 mmHg and was surprised that blood to my glans was never fully cut off. Was able to plough through until the 30 minutes mark. However, my base circumference hit 7’inch mark and felt really fluffy. Pretty sure this is edematous fluid. How to differentiate edema vs true engorgement? Should I just cut down total duration while keeping it at 20 minutes?