I CAN'T ACCESS MY MAC! STUCK ON WINDOWS 7

I installed windows 7 on my macbook pro 13inch retina 2013 edition, and up until yesterday everything was running smmoothly and it would only boot up into windows if I held down the otion key and selected the drive myself. Today though (11/6/14) i went to normally boot up into y mac and it booted up straight to windows, and ive tried everything now, not even holding down the option button is working and I cannot access my Mac partition no matter what i do, ive been trying for countless hours to do something but nothing. I've also tried to use bootcamp within windows but no matter where i look, in the control panel or the task bar, i can't find it and to me it looks as though I have lost my mac 😟 somebody please help me. I've only had this computer for 4 months and if its already not working i don't think id go back to macs,