New onset blurred vision and headache; Call your physician-if he/she cannot see you today...the emergency room is a good idea...today.
If its old-call your physician and set up an appointment soon.
If it is old and your doctor has treated you for it previously-make a return appt to let him/her know the treatment is not working.
If you have complained to the doc before and are not being taken seriously-get a second opinion/new doc.