Yea, you probably bruised a few veins. Jelqs are well known for doing that....another reason I don't do them. The spotting is from ruptured capillaries...also common from jelqs. With jelqs, you're rubbing your hand under high pressure across the surface of your penis and into the semi-deep tissues. Bruising is a highly likely result. Any intense girth exercise can cause such things because you are forcing blood to expand your penis, but from what I've seen with actual experience, jelqs are the most likely to cause these issues. At least you don't have any thrombosis, a clogged vein due what is basically a vein rupture and internal scabbing of sorts. Those suck and take a couple weeks sometimes to clear up. They are also more often caused by jelqs. I'd suggest less intense jelqs if you do decide to keep doing them.
Ulis, and two handed squeezes have given me most of my girth so far. About 3/4'' of the 1.25'' I've gained. I've come to the belief that manual girth work is superior to clamping for many reasons. The two I can think of off the top of my mind: Much less potential for bruising. Clamping traps blood not only in the penis, but the skin as well. Oxygen is deprived from the blood in the skin....resulting in the bruising. It is usually permanent and no amount of massaging, oils, ointments, etc seems to remove it. Clamping (for me) is limited by the amount of blood you trap in the penis. It's much easier to increase the amount of blood doing manual exercises with kegels than with clamping. It's also much easier to increase or decrease (and more quickly) the internal pressure when using your hands. Either method can be dangerous of course...and it's debatable which is ''more'' dangerous...but overall the manual exercises are superior overall in my book. Some will argue otherwise based on what has worked for THEM, but to each their own.