Red dots are busted capillaries. It means that more blood than your penis can naturally handle was forced into certain areas, resulting in the bursting of capillaries, the web-like channels from the arteries into the the rest of the skin/fat/so-forth. A little bit is fine. When you do PE you are damaging your unit so that your body can repair it stronger. If you have a lot, like I do when I overdo girth exercises, then you are overtraining and that's bad. Try to have very few or none at all, and wait to heal until you go at it again. If you are new, then you probably don't want to avoid it, but a tiny bit is fine. When I first started I had little bit from jelqing and then stopped shortly afterward.
