where are you currently on this cycle,wk ?
How long are you planning to run it?
Not every one has joint pain from winstrol,it might not even be a problem but I have heard guys using joint sups like ostyo-biflex and other shit like that.Maybe look it to that.Joint pain def is possible with your cycle bc both compounds are low aromastizing compounds.And I suspect this is the reason behind joint pain.
As for stopping the winstrol before the prop & mast IMO not necessary the both are propoinate esters so you can run the winstrol right up to pct.Winstrol has a half life of about 8 hours