Kurisu;
I believe one medical diagnosis for what you experienced could be a classic panic attack. They often occur for no apparent reason or could be caused by a sudden and unexpected sound (the door) that triggers a basal response that can be quite intense. The symptom of shaking and tingling could be caused by a sudden release of adrenaline, and the crying could be the result of the "adrenaline crash" toward the end of the episode.
Or, you could have had a very interesting paranormal experience.
Or both. Her mind could've compounded the effects with her physical response. Panic attack induced by a paranormal experience. Just throwing out possibilities.
Regardless if you experienced it, then it was real to you. If anything else happens let us know, but my guess is it was a one time thing if nothing has ever happened before