When I first played Sonic & Knuckles (the second Sonic game I played right after Sonic 2), those vines were a pain for me. Whenever I got stuck, I kept moving with no luck. I just basically shut off the system. This was when I first started playing the Sonic series, so I didn't think of using the Spin dash to cut me loose.
Didn't notice that before (the eyes bleeding), but you're right. In the game, the "warp ring" is not only brighter but constantly flashes different colors. Sonic must have blocked his eyes before he went into seizures.