Burn on top of a burn?

So, in my regular fashion I whipped up my usual remedy for sunburn on the weekend. I cut open a fresh aloe leaf and scoop out the gel, then add one drop of lavender essential oil. This usually works really well for me. This time I had a new bottle in the cupboard waiting for its multitude of uses. I put on my trusty remedy and it stung like heck... I thought I spent a little too much time in the sun, but nothing serious ( for a redhead it seems like enough time to water the garden without 45 sunscreen can be too much time in the sun these days!) , but it felt like a really awful burn now... stinging like a regular kitchen burn. I thought it seemed weird that the sunburn seemed to be " showing up" so fast all of the sudden but thought nothing more of it, other thatthe fact that it was hurting so much. I woke up the next morning and everywhere that I put the remedy I had a bright red dry chapped burn, which included around my eyes. It seemed weird because I had never gotten a sunburn so close to my eyes before. Finally today, as the burn is looking worse instead of better and unlike the regular course of any sunburn I have ever had, it dawns on me that this looks like a chemical burn. ( I was freaked out about it thinking that I was having an unusual reaction to the sun and googling lupus symptoms... darn internet!!!) This can happen sometimes when solvents or chemicals are added in the oil distillation process, but the company I use states that thier product is guaranteed 100 percent pure. I wrote a letter to the company just in case they get any other complaints. I patch tested the aloe earlier and have no trouble with it. I just bravely patch tested the lavender on healthy skin and it seems ok so far... but I can't exactly replicate the damaged sunburnt skin... nor would I now. But it doesn't look as if I am having an allergic reaction to it at all. Thank goodness I didn't use this on the kids or on a larger burn. Lesson learned... be absolutely sure where the product I am using comes from. So disappointed! Don't know if this shows it well but you can see the big patch where I applied it... it looks awful in person and is still very angry and red and really painful.