If the coming amount of the pepper spray is not that much, it will not cause the blindness. It is normal for your eyes to get red and painful when the pepper spray gets into the eyes because of its stimulating materials. You should wait for a moment after the immediate wash. You could use the warm cloth to cover on the eyes to release the painful symptom.
Pepper spray into eyes will cause a lot pain in the eyes. Just a little spray could make your pain in eyes last for a few minutes. A large quantity of pepper spray could cause strong pain in eyes which will last as long as one hour. If it is very serious, it can cause temporary blindness. The only thing you could do is wash the pepper spray out with running water immediately, but the pain and burning feeling will continue. You can try to put some ice on eyes to relieve the pain and burning. Even you feel the pain and burning is gone, you'd better let your eyes have a rest. If you keeps feeling the pain and burn, your eyes are swelling or develops chest pains, a cold sweat, pillow breathing or fever, which make you feel awful, go to the hospital immediately.
There is no need to worry about the blindness because it will never happen to you.
It is just pepper, not any chemical stuff. And take into account of your immediate washing; you can recover soon than those who didn't do that in time. For the continue pain and red eyes, it will be disappear soon. But they will be fine later when your eyes finally release.
My suggestion is, which is based on one of my experience, use some eye drop to assist the natural release, and then close your eyes for several minutes.
Don't worry! Be careful in the future! Good luck!