The most commen thing to treat pinched mantle is a freshwater dip. I will have to look up info as it has been a long time since I have done this but you match temperature and then dip for 15 minutes I think? I will check on details and post here.
If you want to attach the pic from your computer, press on the manage attachment button when posting and upload the photo. If you want to instert an iomage like you tried, you need to host the image on a website like photobucket then insert the web address into the image link.