Why am i so clumsy? i fall all the time :PPP?

i wasnt this clumsy wen i was a kid i just started a few or two ago...... every day in school i almost hit somebody atleast once or i do hit them and i fall atleast four times a day and i hav to look at the stairs wen i walk down to make sure im not falling! im getting a rep as a clutz people even think im faking!!!! i wood try to stopp my self but i dont know im falling til im on the ground :PPPP becuz i fall so much i just laff at it instead of feeling embarressed :PPPP i even accidently hit people without nowing until i hit them if there is any lil bump on a flat surface i trip on it :PPPPP sooo why am i so clumsy!!!!