I looked into your signature and the site you're linking to isn't using HTTPS.
Images hosted on sites not using HTTPS will not show on sites using HTTPS as Chrome, Firefox, Safari etc will block them as it sees them as a security risk.
Try using a site like Imgur for hosting your images. Imgur uses HTTPS so images hosted there will show fine.
Thanks for the explanation Ed. This is something that recently changed with this site. I'm not going to start moving where my pictures are hosted though. If they show up, that's fine. If they don't, well that's OK too.
Have a great day!!!