Confusion Over Intense Experience During Meditation

Today, I sat for a 30-minute meditation session, and towards the end of the 30- minutes (since I heard the timer bell ring a few minutes after the start of the experience), I started to feel an intense acceleration in the mind, and just after that, everything else clearing out of my mind. At the same time, I felt my heart beating faster and I am making heavy breaths. I could really pay attention to the heavy breaths and I was keeping my mind there. And then, I saw some soft, satisfying light, lighting up from beneath my eyes (like lighting a torch from below when your eyes are closed). I got really scared of the entire thing, I tried to continue, but I couldn't because I felt I was going to blow up and ended the session. The whole thing was not a calm experience. It was like a free fall. Is this something normal or something that I should be worried about?