Intercoastal muscle spasms?

In the past some have gone to ER just to make sure chest pains aren't heart pain..
I think all that did go testing showed heart was fine.

But monitor your self and go if you feel you need to. better safe than sorry for sure - yes..

I would try all I could to rest/relax the muscles and see if the feeling fades or not. Warmth, some massage, lymph drainage...