Yes you can. There are a number of things to watch out for.
The worst are pressure blisters. When pumping that long if you over do it you will trap lymphatic fluid just below the surface of the glans. They take two to three weeks to heal if they get more than 1 or 2 mm in size. And if they pop or you rupture them you have a big risk for infection. Your partner won't be happy.
The easiest way to avoid pressure blisters is to go slow. Stay under 5 or 6mmHg.
Minor discoloration can happen but pink spots are a sign of blood under the skin and a sign you went too far away to fast. I rarely get these.
You'll also end up with fine wrinkles on the glans as it stretches, but they're mostly cosmetic.
Tube fogging is also a problem. The low pressure combined with the water from the air or any lube you used can cause the inside of the tube to fog. This is an issue because it prevents you from checking for potential problems. The solution is simple. Heat. Either a hair dryer or a heating pad work great. Just warm the tube and the fog will go away.
Be safe, be good to yourself and have fun.