Single Arrow turns into a double Arrow

[ATD Signs]

So I did up a layout today for a customer's sign which I added a couple of directional arrows
pointing in 1 direction. Saved the file and exported it in order to email it to him. when I open up the file again
the arrows now have a point on each end. Has this ever happened to anyone else before? Is there
anywhere I can look to find the cause of this problem. Thanks for any suggestions

 

[FireSprint.com]

Not sure what you mean here. Do you have some photos or a video showing what happened?

 

[Gino]

Nope, not unless I put it there. Don't know how something can be added without some sorta input from a keyboard. You must've hit some kinda shortcut by mistake.

 

[klingsdesigns]

I saved a file today and this happened when I re opened. The file has arrow on each side of rectangle.