Since its been several days that you received the burn, the damage is pretty much already done that will be done. If it happens again, you can minimize the degree of burn by applying cold water to the area(s) burned. That's why your first reaction when you burn your finger on a boiling pot is to run it under cold water. With a sunburn, your skin continues to "cook" for many hours after you are out of the sun.
No, having swollen legs won't pose any serious health threats to you other than being annoying and uncomfortable! :)
Putting the Aloe Vera gel on will help it not hurt so much especially with the lidocaine in it because that is a topical anesthetic. Also increase your water intake to help move that fluid out of the tissues and help with healing. Avoid sodas (especially diet) and high sodium foods and drinks, so basically nothing canned or pre-cooked or pre-prepared foods. Fresh or fresh frozen things so you won't retain any more water.
Remember that the more times you are sunburned, the higher your risks can be of getting skin cancer, so wearing sunblock will literally be saving your life, not just keeping you from being burned!
Good luck and I hope you feel better soon!
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