Tingling during meditation

I have never really meditated other than a few times in group led meditation (short) and had a few things happen that I would like to share and find out if others have had similar experiences.
I noticed this past time that my lips started to tingle for a very short time- through the rest of the evening I felt a slight pressure (not quite tingling) at the back of my head. Also, during the meditation I felt an incredible warmth on both sides of my (mid) shoulder blades.

Aside from any medical issues - are these some common things that can happen when meditating?