I accidentally took double my clonazepam dose of .1 mg?

Isn't that a small dose? 1.0 or 0.1

HI, Mealtop!
0.1mg is a low dose... do you possibly mean 1mg? Either way you'd be far below the maximum dose of 4mg/day.
Not being used to it you might feel very tired, dizzy, and possibly uncoordinated and should avoid any activity that involves physical or mental acuity.
An ER visit is probably not necessary but do you have someone there to watch over you? If you feel extreme symptoms don't attempt to drive yourself. You could also try calling your doctor's office... even if she/he is not available there's usually an on call doctor covering who can give you professional advice.
Best regards and I hope all goes well.