when a chakra expands to accomodate a new level of energy input it is common to feel tingling at the edge of the expanded edge of the chakra. as your molecules, cells etc are not actually connected except by electrical impulse or information when stimulated the 'conversation' can be quite noticable, to feel energy of others or environments it is vital that we allow that energy to permeate, it is information which is shared with your cells. long winded way of saying your body is vibrating in response to an exchange of information, all information is transmitted 24/7 but there are times you may be more alert.

I like the nose bit, ever heard the saying 'got a nose for opportunity, or trouble'?

another time tingling can be felt is of course when sharing energy with others, as in a healing, sharing by the way includes receiving in my book.

and yet another time if it is feeling a bit restricted can be when there is a conflict, for example if you are expanding your heart chakra say, and at the same time have a fear of being hurt, you may feel the conflicting energy in that centre.

it is neither good nor bad as it is really an indication of awareness, it can however be valuable in evaluating your own energetic state.

Tingling happens to many a psychic/medium without the use of chakra openings.

I have been having this tingling as well. The man I see told me I can use a bath of sea salt and baking soda to eliminate any of the negative energy from me or others.

Yes I get the tingle running across my forehead, When I feel I am connecting with someone, I've related it to my third eye chakra opening, I still get this feeling even though I haven't practiced or maintained myself.
I do know that before I'm about to experience a confrontation with my mother, My Jaw will begin to hurt, A sign of communications being blocked or with held. I thought I was having teeth problems until I noticed that my jaw would only begin to hurt before she appeared. It no longer happens.
Sensations happen before an event takes place, I believe it's a way of ourselves to communicate with ourselves,

So, wait. I'm confused.

Why do we have tingling sensations? Because we're opening our chakra? Or because we're connected with someone?

I get tingling sensations under my skin on my left ring finger. It's always and only that finger whenever I think this thing being gone forever and other negative thoughts.

I don't know much about chakras, but we don't have a chakra on our hands, right? I thought the chakras are in the middle of our bodies.

I always got the tingling sensations, but every time I think of negative thoughts about that thing, my left ring finger starts tingling. I thought it was medical, but the doctors and I haven't found anything wrong with me.