Lightheaded, sweat and rapid heartbeat!

Hello everyone

Im 12 weeks pregnant, I’ve been feeling great throughout these 12 weeks, I cannot complain about anything because it’s been nothing but exciting BUT today when i was out i had this episode when I felt very lightheaded, i was sweating like crazy and my heartbeat was racing, I thought i was going to pass out but luckily I found somewhere to seat and had plenty of water, It lasted for like 5-10 minutes and I felt good after but it happened again an hour later. I just want to know if this is normal or has anyone of you experience it. I would really appreciate your opinion as it got me really worried x