This is a physics undergraduate. So I didn't decide to apply for a PHD program until the end of my sophomore year. I am now really concerned and anxious about the amount of research experience

So my question is: Usually, how much undergraduate research experience would be good? I have read the application profiles for many times and it seems that most people got much more research experience than I would do. Let's assume VIP does not count as research, then does "2 semesters + 1 summer" seems to be too little? But if I work really hard, would it make up for my lack of time?
Thank you so much for reading my questions and I would appreciate if you could share your opinions.