which you have develop, if superficial than there is no problem for the chances of DVT.
Apart from this other factors which make the chances for the development of DVT should also be not with you. Like coagulation disorders and other chronic conditions.
The chances of DVT is there when there are bone fracture
and since you are saying that you have only bruised your leg and able to walk, than in my veiw there will be most probably no chances of DVT becuase of this.
Thanks and take care.