Dizzyness in pregnancy

Hi I have just recently found out I am pregnant, I already have 2 girl 8 & boy 4, I have done an accuracy test which has said I am 3-4 weeks! The problem is over the past 3 days I have been feeling very dizzy in a morning, when I get up. It is actual starting to frighten me, I have checked on these websites which say u can experience dizzyness but normally at around 8 weeks? I never experienced this with my other 2 children? Has anyone experience this so early on? I have the metal taste in my mouth which is really strong as well, not been sick just felt it? Is this the norm so early on in pregancy? Please help to put my mind at rest, cos the dizziness I don't like at all! Thanks Julie