Dimension line randomly somewhere in model space

[Anonymous]

My dimension line is doing weird things. I click once and it automatically goes somewhere in model space. Even if I typed in the dimension I want, for example: 10", it goes somewhere and dimension becomes like 101'-20". 

[pendean]

A video of the problem in action would be a better thing to share: here is a freebie app to do that https://knowledge.autodesk.com/search-result/caas/simplecontent/content/download-autodesk-screencast...