Hi, I'm 21 And I Had Protected Sex On Friday

Hi, I'm 21 and I had protected sex on friday 8th April, my period was due to start on Tuesday the 12th April, however now it is the 15th and still nothing. However The past few days I have been experiencing really watery and almost constant discharge with no smell, but I did notice some more yellow lumpy bits there too, again not smelly. I'm not sure what's happening and would love some expert opinion