Submitting form to a route causes file download, possibly Intervention bug

I'm not sure what is going on so I'll try to explain it to the best of my ability. I'm using Laravel 5.5, and I installed the Intervention Image Library package. I followed the instructions on their site exactly. I then did a test image resize in a controller that I setup. The controller was created as a resource controller. I built a form that submits to my controller's "store" method. While testing, I was using the dd() function jest to see what I would get back from the Intervention Image resize() method on an uploaded file. I didn't yet know how to use the resize method so I got back an array that had data somewhere that showed the image was scaled to a very strange size. The major problem though was that the next time, and every time after, I tried submitting the form again, the browser immediately downloaded a file and did not perform the actions in my store method. The image was at the weird dimensions that the dd function showed. I removed the code in the store method and tried again, but still got the immediate file download. I tried loading it in a different browser, same issue. I even removed the Intervention package but still got the same results when trying to resubmit the form. I'm using Valet, and thought that restarting it might help, but it did not. I then rebooted my computer, and still have the same issue. I have no idea what else to try? I would post code but I undid everything and cannot get it back now. Anyone have any idea what's going on?