Is my baby going to come early ?

Hello , I might be totally over reacting but because it's my first baby I don't know what to expect , my baby boy is due 9th of December , I went to the midwife Thursday she told me the head was down already , also my milk has came though , and having awful. Brixton hicks , is there any chance my baby could come early ? I'm also very very big for 26 weeks ! Should I start to pack my hospital bag now ?