You are activating your 3rd Eye Chakra and exerting intense energy into that region. I used to have a strong feeling in that area as well, sometimes so strong that it lasted for days after the Phase Session. It will calm like all the other things Astral related symptoms with practice. Congratulations you are showing positive signs of advancement.
Safe Travels

Yeah I echo that, it can also happen when your awareness to spirit people is growing, I often used to feel pressure on my third eye chakra when spirit people where near. It would almost feel like some one was touching it, but im sure its just the energy
