The meaning of estar lechando?

hey! ok well i know this is a bad phrase because during spanish we were talking about a girl who broke her leg and made the teachers bring her work downstairs and our teacher said that she was milking it. and we were all like hmm what would that be in spanish and so we were like "est� lechando!!" and my teachers burst into laughter and was like that is bad dont say it again! and we have a girl in our cl from guatemala and she didnt know it and our teacher said she wouldnt because it was only used around venezuela. so... what does it mean?? im so curious! thank you so much