I am 18 weeks pregnant and noticed an increase in my pulse rate with some minor palpatations (about 3 per day, some days more, some days none). I figured it was because of increased blood volume because of being pregnant. He had me do an ekg, but during the ekg, I got so nervous my heart rate was 130 (I get doctor phobia). He told me I have sinus tachycardia and wants me to see a specialist. Well, then I started to really panic. The palpatations seem better, but my heart rate resting is between 90-110, its not pounding, just fast. I feel great, but this is giving me lots of anxiety. Blood pressure is fine. Please help! what is sinus tachycardia and is this something I should be concerned with???