He sounds like a great dog so I'm thinking he's just being a 'rude' pup that needs continued socialization and training rather than really an aggressive dog.
Are there classes/instructors in your area you can see this week (sooner the better to start getting a handle on this before a bad habit gets worse)???
MACH3 Bretta Lee Wildhaus MXG MJG MXF MFB TQX HIT CGC TC
Glory B Wildhaus AX, AXJ, XF
"Behind every great man is a woman rolling her eyes." - Jim Carrey