Calendar hacked?

I was on google and was redirected to another tab where a notification came up about my calendar I clicked away thinking it was one of these scam things but later that day I kept getting notifications from my calendar saying I had an event all these “events” had titles like ‘your iPhone might not be protected’ and there was more highly inappropriate ones. My calendar had events every hour for two days down so I thought after the two days they would be gone but everyday they move on to the next day so I don’t think they are going to stop. There is no options to delete events. I’m not sure what to do