A.C.
For sure bring it up with the pedi. My daughter's head started to get a little indent because I'd put her down on her right side and she'd stay that way for hours. The dr. just told me to start changing around how I put her down so she wasn't getting too much of one thing and he checked her again a month later.
I thought when they are tiny like that they weren't supposed to sleep on the tummy at all. It's been awhile for me, so you should ask the dr. about that too.