(potentially NSFW) Is it weird that I grew from a B to a C in less than a month?

This is Bra sizes people, not grades!

Two or three months ago, I had gone up from an A to a B. And I thought, okay thats normal. Then, about a month later after I had realized it, I had grown to big for a B, so I thought just to change from 34 to 36. That wan’t it, I was then a C. I just barely fit, but that was a month ago.

Now I fit almost perfect into a C. I can still fit in a B but it’s a little snug.

Is this normal?