23 and stressed

Hey i just need to help or guidance because I’m so stressed .

I’ve had lumps in my boobs before and have had them checked out all fine. For about 6-8 months I’ve had eczema on both my nipples and just thought it was build up of my body oil. I thought it Better get it checked and the dr found a hard small lump well you can imagine I’m absolutely panicking now. I’ve been set to the breast clinic I’ve been before so I know what happens but I’m just so worried. My left boob is currently bigger than the right (left is where the lump is) I am 10 days before my period so I don’t know if this is normal. I’m getting pain very dull in my left boob and in both armpits . I also have stretch marks on my left boob and not the other I’m so worried that it’s something serious I’m not sleeping i don’t wanna even look at the boobs or touch them I’m crying and it’s really messing with my MH:(