Lump in right breast, now new burning sensation in left breast

Hi all,

Looking for either advice/reassurance please.

I'm early 30s and found a lump in my right breast 6 months ago, it was very tiny, I have lumpy breasts anyway which I discovered in my 20s after finding a lump and it been checked through the 2 week pathway so I thought at the time it's most likely that and  I am prone to worry a lot about my health so thought it was more health anxiety. Last week I noticed the lump has grown and did see my GP who referred me to the breast clinic, they said it will take a bit longer than two weeks so still waiting for an appointment. 

I am now experiencing a horrible burning and pulling sensation in my left breast, I can feel any lump and just wondered do I bother my GP again with this new feature or just wait until the clinic? Or is it nothing to even worry about. My grandmother sadly had breast cancer so I have always been on the cautious side I guess  

Sorry for the waffle and thanks in advance, but wondering if anyone has had this and what the outcome was?