Copyright claims, or content ID claims I think they're called, won't result in anything bad happening to your channel, just to the video itself. The people claiming it can just take away the music or block the video or whatever, and there's no 3 strikes rule for claims. You can make up for a strike after 90 days, where it'll disappear from your channel if you do "Copyright School" which is just like a multiple choice test thing. You could also find the person who struck your video and ask them to remove their strike, or if it was wrongfully taken down by Youtube, you can ask for them to put it back up with a counter notification. I know this was long-winded, but I hope it helped!