I have recently got a electric toothbrush. i've been using it for a few days till i noticed two small brown dot on tooth that wasn't there before?

Brown dot on tooth: There is no way to know what these are without a visual examination. It could be stain, decay, fracture, or decalcification ( a blemish inthe enamal). See your dentist for an exam and diagnosis.

Spots: It is impossible to tell you what this spot is without seeing it. So see your dentist and get it checked. It may be stain decalcifications or it may be decay. Get checked.