There can be a lot of different reasons for a lack of response. Whoever you were corresponding with might have gone on vacation, or the mail server got a little overzealous on flagging things as spam and no one's checked on the spam folders recently... I wouldn't worry too much.
ok guys thx for the input i just submitted 1 of the tests yesterday so only 2 left and i still got 2 weeks now . still no response ... not even something that indicate that they've received my email . should i continue ?? i start thinking that i might be in the spam folder