Q.Over fertilizing flowers
Hi I’m pretty sure I have a fertilized my flowers there really isn’t any growth and what few flowers that have come out have been dry and brown they are in a big pot I can’t really do anything about it I just wondered if I should wait and see what happens or if I should just pull them and get some new ones .? They are Calibrachoa and we are in Michigan zone five so these are an annual

Your plant actually look green and healthy. The spent flowers can be dead headed from the plant.
You can pinch back to a healthy set of leaves to promote a bushier plant.
https://www.gardeningknowhow.com/ornamental/flowers/million-bells/calibrachoa-million-bells.htm