Unfortunately its hard to tell without being able to see a published post...
Do you understand Text wrap and alignment?
example:
Go back to the post editor, and make sure the top right tab is in "Visual" mode.
click on the image
click on the left icon: "Edit Image"
scroll down Alignment:
Left: aligns the picture to the left of the posts and wraps text around it.
Right:aligns the picture to the left of the posts and wraps text around it.
Centered: Centers th picture and starts the text or next image on the next line.
None: simply puts the picture on a line as if were a letter or a word. the next text (or image).
setting the alignment to "none" maybe the way to get your images how you want them. you can experiment from there.
check out the support page
http://en.support.wordpress.com/images/
heading 4 about alignment.
and more directly
http://en.support.wordpress.com/images/image-alignment/
hope this is helpful.