Concern about my IT company

Hi there, I have a delicate question to ask, I am a little worried that the IT company I use might be looking at my private info stored on my computer through my team viewer and I want to know if I can see when team viewer has been used as I know when they had access to fix something. I don't want to cause any issues if there is nothing but want to know as they installed it on my machine and cannot see the user history. I guess this is because they installed it. Can anyone help?