Without seeing a picture I'd say you broke some capillaries. It's dry blood under your skin if it doesn't hurt to touch. If it's painful then it's a bruise. Either way rest until it is gone. Heat it whenever you can with a warm wash clothe, not hot. Heat for 5-10 minutes at a time and then continue with your day. Massage it after heating it. Move in circles applying pressure as if you're trying to move that blood around. That is the idea, to move the blood out of your cock and get it to circulate. The likeliness it will do it on it's own without you massaging and heating is unlikely, the penis has a piss poor ability for this type of thing. Guess it didn't think we'd be pulling and squeezing and pumping it when it was created.
But now you know: Your routine was too intense, stick to something lighter and proven for beginners, air pumping with BATH MATE I mean.. to me it's in the name of it where you're supposed to use it.