Hello. Recently I've noticed a dip in my breast when I lay down on my back. I have the dip in both breasts but one is slightly more prominent and underneath one is slightly more firmer. The dip feels as if its just a hole and has got nothing there. 

When I stand up or sit up there is nothing there and it feels normal. I've looked in the mirror and there is no sign of a dip or dent or any other discolouration and it looks comepltly normal. It's just when I lay down. I usually have this ache in my armpit before and it's gone in a couple of days but recently I had a horrible dream where I was diagnosed and its freaked me out.

I have no other signs other than a slight discomfort in my left side in my armpit but I'm also due on for my period (7 days to be exact) so it could just be that. But I've never noticed this before I a suffer so bad with health anxiety. 

I apologise if this isn't the place to ask questions. I'm so just unbelievably scared and looking for some support. 

Thank you in advance.