You need to copy the link from Tinypic and paste it into a post here.
The easiest way to find the correct link is to click on the thumbnail you see, to make the image bigger.
Then click on that image again, to get a picture which fills the full screen.
Right-click in the address field, to highlight the URL, and select 'Copy'.
Come to an AB thread, right-click and select 'Paste'.
(NB: It's best to put the link on a line all by itself, so that it doesn't get mixed up with any other text)
When your post appears here it will become a clickable link to your image.