Is this a reason for me to not trust him?? Advice please!!!?

My boyfriend just started going back to school, he has a class w/ a good girlfriend of ours, whom is married to his best friend. One day after school the girl calls me and says that she is in the same class as my bf and when she was sitting down, he walked into class (first day of school) and she heard these two other girls, scream our his name and wave hi.. Of course, his not going to talk to them cause she's there or maybe he wouldn't even talk to them either way.. Then she tells me that she told him I better find out about this, he then turned around to her and said dont say anything to her (as in me) so you wont start an arguement for no reason.. Of course my girlfriend told me this, but I can not say anything to him cause I dont want to do that to my friend.. I keep asking my bf so whos in this class and whos in that class, he told me about this girl thats in his other class who works for his brother, but he will not tell me about these girls.. I dont know what to do..Is this a reason for me to not trust him?? Advice please!!!?
Just forget it....don't be paranoid, that's a turn off. Acting this way may create the exact destiny you're trying to avoid. Think about it!Is this a reason for me to not trust him?? Advice please!!!?
He may be guilty of flirting, but thats it.
maybe ur friend is just trying to make a bigger deal out of it then what it really is... I wouldnt worry about it...
Grow Up, thats all tht needs to happen.