It's a little tough, but nothing anyone can't complete. It's the incline from the start line is what creates the challenge. Take my word! I had shin splints for 48 hours. HOWEVER, all due to not conditioning correctly. I was at the gym twice a day for six weeks working out all muscles and putting in the cardio time. What I failed to do was work my legs more. So the moment I was at the starting line, I was ready to take off with all confidence. The very second the gun was fired I took off like a bat out of hell and started to feel the pain a quarter into the 5K. Sprinting in the beginning wasn't the best idea either. Ha.
You'll do just fine. Hopefully during condition, you raised the incline on that treadmill to it's highest level as you power walked. If not, then there's nothing better than sitting on the couch with bags of ice on your shins while you binge on Nextflix and ice cream. Either way, have fun, be safe, and best of luck. The Bridge Run is to help with cancer research so that already makes you a hero!