Sore breasts for nearly two weeks and now have stuff coming out left nipple

I'm 24 me and my partner do want a baby 
​I usually do get sore boobs a week before my period is due but this time it started nearly 2 weeks ago and they are just to sore to touch 
​And now I have clear stuff coming from my left nipple :( 
​I don't really want to go to a doctor I am always there due to my health issues and so on so I want to try sort it myself I'm thinking of giving it until my period is due and if the pain doesn't stop then ask my doctor what's happening 
​I have a gyno appointment Monday morning so maybe he may be able to tell me what's going on I hope he can 
​Please somebody give me advice