It is probable that you are suffering from moderate degree of photo dermatitis
I suggest you to use an effective sunscreen like Photoban lotion. You should also moisturize your skin every 2 hours. So please carry a moisturizer with you always and use it liberally. Use it at nights too before going to bed.
For the bumps to disappear, you may apply calamine
lotion to the affected areas for a week now.
Do not worry; you will be fine soon.