I took my battery terminals off to clean them and when I was tightening the negative side post, I noticed as it was getting tight and i gave it one last turn and then it started feeling loose again. So I retightened it and left it when it felt snug. Im sure it wont hold up for long. Will I need to get a new battery sence i might of over tightened it and it may become lose..
If you stripped the inside thread there is a chance you can drill it out, re-tap it, and either install a helicoil or use an oversize bolt on the terminal. If you spun the battery lead post within the plastic housing you probably need a new battery. If this is an older battery (5 years +) I would just get a new one.