Haven't felt the baby move today. Should I worry?

I'm 18 weeks and 4 days today. I've been feeling my baby move about 10-30 times every day since 14 weeks 5 days. They are very tiny movements but I do feel them every single day. Yesterday, it was the first time I felt a huge kick. It was such an incredible feeling. However, today I haven't felt my baby move. Maybe just a couple of very small movements. Definitely much less frequent than usual. Is it normal?