I'm a right in saying the "attachment" tab is only available when making a post on a thread - I can't see it for adding a picture in a PM.
Do we still need to use someone like picture bucket for private messages?
Yes, you need to do this before the upload. It may look correct on your phone/laptop etc, but unless you have specifically rotated it to the way up you actually want it to show, it may not work. Sounds daft, but it works.
A couple of people have reported problems uploading images today. I can upload some images but not others, there seems to be no pattern to it (size, ratio etc.) Hopefully it is just a blip but I'll keep an eye on it.