Is It Possible To Create A Normal, Healthy Relationship When You Have Sex Early On?

I just started seeing this guy and we get along really well and the sex is fantastic. We are both in our 30s… but there is a worry in the back of my brain that since we had sex quickly, it will fizzle out quickly. What do you think? should I worry about it? or not worry and enjoy the how nice the relationship is right now?