Featured product picture problems

Hello! My website is cherrybombclothes.com

Here is the issue I am having, whenever I put a featured product picture using the ‘products’ tab (like i’m supposed to), the resolution of the picture gets screwed up somewhere along the lines. If you go to my ‘shop’ tab, I have posted 2 pictures of the shirts using a different method of posting the pictures and they turn out just fine. However, the bottom one is ‘featured product picture’ function. The resolution or dimensions (I’m not sure which) gets screwed up.

Things that I’ve noticed so far:
1) if you inspect the elements of the image, it’s a 268.567px image. Which is odd, because I’ve never uploaded that particular picture in that size.
2)If you copy the picture, and then paste it in MSpaint, the picture is 100x100px image, almost like it’s a thumbnail being blown up. (Which also happens to be a size that i’ve never uploaded)
3) If you left click the shirt, you’re taken to a page where an enlarged (however still very pixelated version) of the shirt sits.
–repeat step 2 with this new picture and the dimensions are 200x200px. I don’t know why this is.
–still looking at the enlarged picture (the 200×200 one) I’ve set a picture gallery using the same image in various sizes. ALL of them turn out just fine, and look like I want them to.

I’ve tried messing around with the media settings on the side bar, I’ve also tried rescaling, cropping, and various aspect ratios with no avail.

Is this an Id10t error, or an actual problem?

Thanks for reading, please help!

-Landon