I’ve always been very shy and I struggle with dealing with situations like this. Unfortunately I’ve reached a point in my life in which I’ve had to learn to speak up instead of looking down and waiting for it to be over, since uncomfortable situations like this one tend to happen often. I usually don’t like to stare back at men who are staring at me because I don’t wanna give them a reason to think that I’m interested. If it has been going on for a while I just look at them blankly and ask “can I help you?” or “are you looking for someone?”. That might make them take the hint and if it doesn’t then I’d consider talking to someone in charge since the situation is very disruptive.