Well Stds can not survive long outside. I don't think you can get Stds from licking dry blood because it needs blood in order to survive. Just get yourself checked out just in case.
HIV does not survive long outside the body, but the viruses that cause Hepatitis B and Hepatitis C can survive much longer. I think if the bodily fluid has dried, the amount of virus decreases, but it's not zero. I really do not know much more about this.
Good luck,
Em