It is your heart chakra that needs clearing, often times you will get pain cause there may be unresolved issues that need to be dealt with.
Best thing is to keep meditating and imagining the blocks are shifting with the green energy you are taking in.
I used to experience the pain initially and then when I carried ormus around in my bra it opened my heart chakra so much it literally felt like I had no skin or bones around my heart and I had to keep my arms over my chest it felt so exposed. Was a very weird sensation, anyway when it gets to the point the energy is flowing freely, in and out you will beable to actually sense the energy moving and swirling away from you and around you.
Work on the torsion field in that heart energy moves clockwise and energy field move it anti-clockwise, its a great sensation. Then imagine a pyramid on the top half and then add the bottom half and you can work on your merkava or merkana or whatever its called now.