I have had somewhat of a similar experience to you. CD is correct that only you can decide what the truth is about your experience. But, you will not find a spiritual experience as a possible diagnosis from most mental health professionals. If you do seek further counseling along those lines to try to sort it out, I suggest looking for someone with a balanced view with some background in spiritual crisis counseling or someone more open to other possibilities, even clergy. Otherwise you will likely get more of the same, i.e., here's some drugs for your condition with little helpful discussion about what it could have been, what led you to that state. I'm not saying don't follow your doctors' advice; only maybe look to have an alternative view point as well.
For me, I have spent the last six years pondering my experience. I come from a scientific background rather than a religious one. I read crap loads of books and articles on all sorts of topics looking for an answer. I read scientific ones that sought to explain the chemical aspects of religious experiences and mental illness, anthropological works on the evolution of the god concept, anecdotal stuff and self help (I found Kundalini Rising very interesting, also After the Ecstasy, the Laundry was helpful), and lots of stuff on paganism and spiritual fiction (Life of Pi, The Alchemist). I found these great people on this forum and I stumbled into shamanism. I talked the ear off my counselor about it for years. I still can't tell you what it was, but I can tell you it wasn't manic depression in my case though they thought it might have been. But I have been forever changed and now I have come to accept what happened. It takes time to come to grips with such a mind blowing and traumatic experience as you have had. I remember feeling like I wanted an explanation and right away-- it really tore at my gut. But it is OK; in time you will get to your truth. What I found most interesting as I researched away was the commonalities between my experience and those of others-- your story is another reminder. I was not alone and neither are you. Surround yourself with people who love and support you, listen to your heart, and give yourself time.
I hope something in what I have said is somehow comforting.
Blessings, EM