Fainting..

I’m 14 weeks and 3 days pregnant. This morning I was going to the bathroom and started to get really hot, dizzy and nauseous. I tried laying my head on the sink, but my ears started ringing and I saw this neon yellow circle in my vision. I pulled my pants up, and next thing I know I’m waking up on my bathroom floor. I don’t think I hit my head or anything, nothing hurts. I’m just nauseous and shaking now..is this normal?? I plan on calling my dr..

Update!! Thank you ladies for your advice. I called my dr and they said the same thing about low blood sugar. They recommended keeping a snack next to the bed and eating that before I get up.