The leaves on my Meyer lemon tree have suddenly started to spot yellow, with some spots turning brown in the middle. My tree is over a year old now, grown from seed (was gifted to me when very small) and has had some yellow leaves, at times dropping, on the bottom of the plant for some time now. Now the leaves on top are getting these spots as well as yellowing from the tip. It's in a bright window and watered when dry, around once every week and a half to 2 weeks. I do spray it with some water in the mornings, and I'm wondering if this might be the cause? Thank you for any help!