Delirium - I have to address your second question first because this is the first time I have ever heard anyone describe this.  I have had this feeling quite often while growing up and it really kind of scared me.  I only have it very rarely now and I get a real feeling of being connected to something that no-one else recognizes.  Kind of like a door in my mind has been flung open and I'm supposed to be doing or picking up on something that I'm not recognizing.  I have never told anyone about it before.  If you learn anything more about it please let me know.  I would love to know what it is all about.

With the tarot cards, I think we are all connected in some fashion that I can't describe.  I am not articulate enough to explain it well, but I think that all the information that we could ever ask for is out there we just have to access it.  When using the Tarot cards that is what we are doing, we are accessing the information that is inherent in the universe.  When shuffling we ask our questions and our subconscious receives the information we need and we unconsciously "stack" the deck to show us what we need to see to interpret the information.  If that makes any sense.  Not everyone believes it the way I do, but this is my belief.

Best Wishes
Louise

To answer your second question first The Tarot opens up a door to the psychic I would take a guess as it wasn't my experience that the feelings were caused when your highly developed intuitive skills were kicking in
I would suggest that before picking up your cards you enfold yourself in a cloak of protection this will protect you from negative thoughts and energies When we read the cards and your gut feeling is telling you different to the cards meaning we go with our feelings as this is physic and it knows best with me its part of the picture only that i notice sometimes and that will give a total different meaning to the cards interpretation
In response to your question do our guides help use read the cards i would say yes they can if you ask they do not interfere with your free will so you do have to ask  
As far as other spirits coming through- you have a door keeper unless you invite spirit through to participate in the reading your door keeper will keep them out
I'm a developing rescue worker so i can pick up on energies really well so the information i have given is from my experiences I have never had unwanted spirits help with readings

The tarot, crystal ball, palmistry, astrology, all paranormal practices, are tools to the psychic of the human being.  The first tool is yourself.  Opening to spirit is not for the feint of heart.  Letting the fears go is imperative to understanding yourself and then who you are on that sensitive level - psychic.

I often feel that sense of hyper time, it is almost like the moment is surreal... Like watching a dream or a movie. I feel it more at certain times of the year and month. I am not sure why, but I think that it is when I am more open to it. I am still learning about the many things that I can do and trying to develop them. As for the tarot, I read, and I have meanings that are associated with the cards, which are from the book that I got with them though I often tell people something different. It depends on the cards and me and I am guessing the spirits who are helping me, I have on a few occasions tried to do readings only to forget things that come naturally to me, I usually tell people that I can't do the reading and pack it up. I often get complaints about that or refusing to even attempt to do the reading. I am unsure who I am not reading for, me or them. Somethings I am just not meant to do; I just try to deal with it as gracefully as possible.  As for the hyper time, try recording the thoughts and feelings you have while it was happening as well as the things going on, it might make more sense if you read it after a day or two has pasted and you are not so much in the moment.

                                         Good luck to you on all of this.
                                                                                      Nyte Shade

There is no time in spirit.  That means that when you are using your spirit self to gain any information (as in mediumship, psychic, intuition, empathy - any paranormal tool) it is timeless.  You will have the sense of no time passing, or much time passing - all not sensed right within the physical/material vibration.

The tarot is a tool.  When using it and you 'feel' unconnected with the client, it is best to move on and be honest in your evaluation.  Nothing worthwhile comes when you know it won't come.  All tools are about trusting your own instincts.