This kanji uses the kun'yomi readings for each kanji, for some reason. You learned the kun'yomi reading for 戸, but in this case it's rendaku'd so it becomes ど instead of と. You didn't learn the kun'yomi version of 井 with the kanji. Think of this well, and look inside. There you see an eagle (い), stuck inside. As you pull it out, it scratches your eyes out.
When I drank cold water from the well, I got brain freeze like when I ate cold ice cream.