if the wound gets infected, your char will tell you the wound feels itchy and stuff. i guess, the only thing against moaning are painkillers.

s.o. posted this code snippet on reddit, which explains this:
http://pastebin.com/gTRgcyjT (found here: http://www.reddit.com/r/dayz/comments/1vbhyg/this_is_why_we_rubberband_nooby_devs_remove_this/)
If your data could not be saved on the hive for some time, you may have moved >1000m and therefore get teleported back and have to restart your game

According to some youtube-videos, you get unconcious when <500 Blood.
Some people here stated, they were able to regain conciousness after a blood bag/saline bag. Maybe they just got over 500 Blood again?