My mole was darkish brown and looks red now.. is it normal?

At the age of 19 with the mole present either since childhood or teenage, expect the colour change that you describe to be very normal and not a sign at all of a potential malignant mole melanoma. No worries please

Rapid changes in moles may reflect traumatic events, such as irritation or bleeding and having your dermatologist reassess is always a good idea, specifically if they continue to grow.