Hi! My name is Anna, "You'd really like me if you got to know me. I've known me for years and I love me."
Currently it is a bit hard to figure out who posted something originally (unless you click on 'reblogged from' often enough to get there and then reblog it from there which can get a bit tiresome if the post has been reblogged very often).
There is a way to include the original source in your post so that everybody can see that this is your post. It's a bit fiddly (and you still won't get any notifications if somebody reblogs your post from somebody else obviously) but if you like to know people that this is your post it's the only way (at least currently) and it takes only a few more clicks.
1. Write your post and post it like you normally do
2. Copy the link of your post (right-click the title of the post on your dash and hit 'Copy Link'
3. Hit the 'Edit'-button of the post in question.
4. Copy the link in the source-box the right side of the screen:
(right click and 'paste')
5. Post again. Now it should look like this on the bottom of your post:
That link will remain there even if reblogged.
(You can also get all this without the editing if you make up a custom URL for your post and past this one in the source-field when writing the post)