I am the community leader in the STD forum, I know how STD's are spread. This is not a risk for a STD for many reasons.
http://kidshealth.org/teen/sexual_health/stds/std.html
http://www.womenshealth.gov/publications/our-publications/fact-sheet/sexually-transmitted-infections.cfm
No, you can not get a STD from that.
Yes...anytime you come in contact with someone else's bodily fluids unprotected, there is a chance of contracting something.