We’ve all been there. We spend too much time at the beach and forget to reapply our sunblock. Or worse, we forget to apply any at all. So what really happens to your skin when you get a sunburn? Is it really that bad?

It depends on several factors: your skin type, the sun’s intensity, and the length of time you spend in the sun. But remember: You can still get sunburned on a cloudy day because UVA rays pierce through the clouds. They also don’t feel hot.

When you get a sunburn, your skin turns red and hurts to touch. Depending on the severity, additional sunburn symptoms can include swelling and blistering. And you may even feel nauseous and weak. A few days later, your skin will start to peel and itching as your body tries to get rid of sun-damaged cells. If they don’t peel off, you they be in danger of becoming cancerous. The sun’s UV rays have damaged the DNA in your skin cells. Sound scary, doesn’t it?

Eventually, after your skin peels (don’t help it along by peeling it yourself – this could cause an infection), new skin emerges. Your job is to protect this delicate new skin by staying out of the sun for at least a week after a bad sunburn. Then, when you do go out in the sun, apply ample amounts of sunblock (SPF 30 or higher). Additionally, wear wide-brimmed hats and sun protective clothing. And remember, five or more bad sunburns in your life can double your chances of getting melanoma, a deadly skin cancer.