How long do the way lines last? Do they move when you move your eyes? How long have you seen the "C"?
Those wavy lines sound like floaters. Floaters are in the central cavity of the eye called the vitreous
. The most common cause is the jelly material that is within your eye that over time condenses together and cast shadows on your vision and can look like fibers. Other things can also cast shadows such as blood or pieces of retina.
The "C" sounds like flashes which is caused by stimulation of the retina. This can happen when the jelly material pulls away from the wall of the eye, a normal process called a PVD (posterior vitreous detachment).
If you are seeing floaters and flashes
with a PVD, then you will need a complete dilated exam to check for retinal tears, holes or detachment. If there are tears, you may need lasering of the retina to prevent a detachment. If there's a detachment, you may need laser, freezing probe to reattache it or surgery if it is more extensive.
Signs of a retinal detachment
is a shadow, veil or curtain in the periphery of your vision. It is key to recongnize the signs of a retinal detachment before your vision is affected.
Again, it is recommended to get a full dilated eye exam to check for retinal problems.
I'll be happy to answer other questions or clarify if needed.