hello and welcome to health care magic,
this may be due to gum infection
please check for another 4-5 days ,whether bleeding is reducing or not as you have got your teeth cleaned.
get the biopsy of the lesion if you have any in your mouth.
since you are a smoker,there is a chance of getting leukoplakic or erythroplakic lesion.
get physical examination done.take tab. microdox-dt-100mg,once daily for 3 days to reduce the gingivitis.
use soft-interdental brush
mouthwash to brush your teeth.
please stop your smoking habit too.