Suggest Remedy For Unusual Spots Appearing On The Hand

Hi,



I am 32, 5'10, 155lb. One morning I woke up with about 15-20 brownish flat spots which appeared overnight on my right hand. It's been about a week with no changes. I don't believe I touched anything different and wasn't out in the sun. They don't itch or hurt, they are just there. The only thing I did differently the day before was get my blood drawn. Any idea what it is? thanks.