I haven't missed seven calls from all of them, its been like this since day one. But if I did miss 7 calls from them, shouldn't it say "7 missed calls" or something? And shouldn't that be on a other entry with just the missed calls?
If you got a missed call notification, head onto the calling list and see the number of times your phone rang before the call ended. You would now easily be able to make out whether it was a long ringing missed call or your buddy left you a single-ring signaling you something.