Product and Gallery Issues

So I am new to WP and I have set up my store and am having a few issues with the product pics.

First, the thumbnail product pics all have a vertical scroll beside them, I have unticked the crop to exact dimensions and lowered my max width to 160 and installed the regenerate thumbnail plug in but none of those things have taken away the scroll.

Also, how do I get multiple pics to show for a single product? I see the insert gallery option when I originally upload the pics but if I didn’t add the gallery before I published the product I can’t seem to get the gallery option again.