Sternum pain from dips, is the adjustment I'm making correct?

I follow Greyskull LP. Wednesday I was doing bench press with a new weight (175 lbs). On my first work set I had my earbud on my chest right where the bar came down and it left a mark on my chest. I finished Bench Press with no pain, however when I moved on to dips I felt a pain in my sternum that I never had problems with, I couldn't do dips or pushups without feeling the pain so I didn't do them.

Friday I did pull ups and push press and felt fine.

Today I did bench press with the 175 lbs and failed my last set ( so I'm resetting 10%), because on my last set the sternum pain kicked in out of nowhere. I went over to the dip bars and sure enough the pain came back, so I couldn't do that either.

From what I've read online it seems like I've overworked some ligaments(?) in my chest so I will be giving dips a break for at least a month and will take it slow with bench press (I'm already taking off 10%). In place of dips I'll do lying tricep extensions with an ez curl bar.

Good idea?