Bad people - 2nd shift maintenance technician Baxter Employee Review

My boss yelled and threw a tool at me in front of other employees. I went and reported it to his manager. A couple days later I was put on a PIP, which is strange since I was still training. After a month I went from being a good worker to a horrible worker. I was let go a week after that. I reached out to HR many times for help but was NEVER called back. Now I'm unemployed and that boss that yelled and threw a crescent wrench at me is still there and even got a raise. WTF!!!!!!! I'm a vet and I've never been treated so poorly. BAD PLACE TO WORK!!!!?!