Group dynamics.... How to tell if people are cool with you.
1) People look away like they are embarrassed and make a point to not make eye contact with you - there is a huge problem and you need to recognize how your behavior is effecting those around you and take steps post haste.
2) All the people around you laugh and chime in in agreement - this means that whatever the joke was about is true, so you better take note of it and react accordingly to smooth over the issue, but it's not a huge problem yet.
3) Those around you tell the joker that they are rude or overreacting - then you don't have a real problem, just that one person is being touchy.*
*If this same issue comes up on separate conditions or with different people, it may be traveling towards levels 2 and 1, so beware.