For some reason my polar tracking wont lock on at the correct angles. I currently have it set for 45 and it will only lock on as showing in my picture. I managed to fix it last night by switching user profiles in the options but it is having the same problem yet again this morning.
I can't see what the problem is from your screenshot but have a little look at the settings for polar, in the bottom right hand corner of the dialog is measurement set to absolute or relative to last segment.
The default behaviour is absolute.
If this has been set to Relative then the angles are measured from the object you select. very clever/powerful but if you don't know what is happening it will confuse