Mucus plug?

I'm 33+5 weeks pregnant and tonight I believe I've lost some of my mucus plug. It was a stringy yellow tinted mucus looking thing on the tissue after I wiped after having a wee. How long does it take to fully lose the mucus plug? Also how long does it take for labour to start after you've lost the plug? I've read up that you can go into labour 2-3 weeks after losing it if it's your first baby. Is this true? This is my first baby so I have no idea what to expect. I had a lot of pains down in my stomach yesterday and a few twinges down below yesterday. I've been getting lots more white discharge recently. Also I've been getting a hell of a lot more tightenings across my stomach over the past few days. Can anyone answer my questions? Many thanks if you can :)  not sure if I've posted in the right place.