I had my first ultrasound today... and I am so scared. What does this mean?

I am NOT pregnant that I know of. I have been doing my tests to see why my husband and I are not getting pregnant. Well I had my first transvaginal ultrasound ever today. The ut scared me because he kept asking me if I felt pain when he did certain things and honestly I don't know what pain feels like anymore so I kept saying no just some pressure and he would look at me like "you don't feel pain?!" Like I was supposed to or something... he said "I want you back here in the morning to discuss your tests"... scares the hell out of me. What could be wrong? Has anyone had the same situation? Do they usually tell you to come in the next day???? I am freaking out