Red Spots (not dots) + grip question

I changed up my stretching routine and I get this crazy bloodflow now before I even start jelquing and I lowered my time to 15 minutes instead of 25, but I was a lot more focused, gripping firmer with the overhand OK grip and going really slow, like 6 seconds per rep, and I had some dots on my glans at first, but a really good warm-down took them away so I didn’t think too much of it.

However, on the third day of this after a couple warm-down sessions I ended up with kind of a red line going up my shaft that wasn’t too noticeable, my dick looked bruised, and I had a massive red splotch right in the center of my head. My dick felt fine, but I took this as obviously overtraining so I’m taking like 4 days off of jelquing.

I’m switching now to a different grip (thumb + 2 fingers, not the normal OK grip), because it just feels wrong to lower my intensity too much with my current grip and I keep increasng, but with this increased bloodflow, it’s affecting me a lot more.

Anyone have any experience with these kind of red splotches/big spots? How long did you rest for? From information I read on here it seemed like a few days was a good idea.

What do you guys think about different grips for jelqs? what do you use?