OK, first off, if your molly has shared a tank with a male within the last 6 months, chance are it is pregnant.
To post a picture that's over the upload limit for this site, you need to get an account with Photobucket, or Flickr, or similar.
When you upload the photo to whichever site you choose, there will be a bunch of codes alongside it. Copy the <IMG> codes, and paste them on here.