Once bitten, now dog shy

I went to a friend's house yesterday. I had never been to her house before and she has a 9 year old Rottweiler. I don't like big dogs. He came up to me in the drive way, and I kind of just backed away. Not trying to show fear but just overwhelmed with a 125 lb dog that if he stood up on his hind legs would be taller than me (yes, I know that isn't saying much but still)...

Later on, my friend got a phone call and I stepped outside to give her privacy, I decided to walk over to the dog and pat him. MISTAKE. RED FLAG. STUPID... He had his back in the corner (mistake number one) and I just walked up with my hand out to pat, pat, pat on his head (MISTAKE TWO, didn't let him smell me first.) In doing so he just chomped down on my right hand and my TIFFANY'S RING... I didn't yell (I don't think), I didn't scream. I just said, "Your dog bit me" and the family was around me in seconds... I noticed my ring was bent so I quickly removed it and had a little in print from part of the ring in my hand... It didn't really hurt, I was just in shock.... UNTIL I TURNED MY HAND OVER... BLOOD EVERYWHERE... We went inside and rinsed it off and I had a deep puncture wound. We cleaned it out and put a band-aid on it and was good to go...

I was impressed with myself for not freaking out - however, I know from past experiences that when I am seriously hurt I don't freak, so I knew I had moderately hurt myself. Today I have a few teeth mark bruises and a little stiffness in my hand. Not bad.

I didn't want to make a scene and make a big deal out of it because I didn't want to embarrass the dog owner because I was a guest in her house. Plus, she has kids and I didn't want to scare the kids. I hope I acted appropriately.