I don't understand how to put the image directly in my message so I posted teh image in the test image forum and I'm trying to link the image. [I hope this works:]

Here is a link that might be useful:

The spots shown in the picture are not all that uncommon. They generally occur when there is a sudden change in the soil moisture status combined with low atmospheric humidity. Unless you see an upsurge of these I do not think there is all that much to worry about. - Millet

With these type of spots the symptoms usually always appear as chlorotic areas on the leaf blade between the midrib and leaf margins that later turn gray to light brown. Following is unrelated to above) On citrus seedlings you should always water in the morning so the sun's rays can dry the soil surface before night fall, to avoid problems with Rhizoctonia, Phytophthora and Pythium fungi. Take care. - Millet

I agree with Millet. I have those spots similar to yours from time to time but I thought those were caused by some insects nibbled at the leaf and it flew afterwards. Unless there are many leaves that are like that, if I were you I won't worry about it. I always thought that there will be new leaves, new growth that will replace them. Sometimes I snip them for good looks and you know what? The plant is forced to grow new buds to replace them.

Anyone know what these tiny white dots on my lemon tree leaves are?