Dizziness

I'm currently 18w 5days pregnant and this morning I woke up and my head was spinning . This is the first time this pregnancy that I've had this happen . Today was my daughters first day of school so I had to push myself to get up and get her ready and Take her. I'm back home and I still feel like my head is spinning but not as worth as before . I drunk some apple juice and had a breakfast bar but I can't even stand long enough to cook anything . My doctors office doesn't open for another hour but has anyone else experience this before ?