Woke up this morning with a small bruise, size of half a pinky nail on my left eyelid. what is it and is it anything to worry about?

Bruise: It could have been from some inadvertent and trivial trauma or from a spontaneous leakage of blood from a tiny capillary in the eyelid. These are more likely if you take aspirin or anti-inflammatory medications like ibuprofen or naproxen. If multiple, scattered bruise like spots or bleeding from gums, nose,etc occur, this would be a cause for concern and would require investigation by a physician.