I usually ask myself these questions when deciding about a dr visit.

is this a new or worsening situation?
did I recently hit or bump the area?
did I do anything to cause a flare this area ?
is there a coloring change - reddish or bruised?
is it very tender to touch?
is there swelling?

Depending on any other info you give to a MD & if they have seen you before or not - it really is hard to tell what they might suggest.

If you had said bright red, very bruised, or extremely tender/sore, or very swollen then a dr appt would be a very good idea.

It could even be the top rib tweaked out of place, most MDs have no clue or real training on that.

An Osteopath, PT , chiro might be a better choice if you think it could be the top rib issue.