You should be fine. Keep in mind that steak can be eaten raw as in steak tartare or yukhoe, and some people like their steak barely seared on the outside, ie cooked blue.
Foodborne illnesses are killed by heat, generally the guidelines would be that in order to be completely safe you'd have to heat meat up to 160F, in other words well done. 125F (medium rare) is nowhere near warm enough to make food safe, yet we eat it that way all the time because it's low risk. With steak most of the time the dangerous bacteria is on the outside, and is killed very quickly by high heat. Poking steak before the outside has been cooked enough can carry bacteria to the center of the meat where it will not be killed by cooking, so it may be worth avoiding doing that if you can.
So it's safe to eat, but may not be warm enough for your taste. In the future I would suggest cooking to temperature rather than time as there are too many factors (meat thickness, starting temperature, pan temperature, air temperature, bone in or out, cut, etc) in cooking steak for time to give a consistent result.