When running out of credit do all the text messages that one writes go to the outbox?

Last night I was supposed to write message telling my friend that I arrived home and when I woke up this morning I realized that message was in the outbox.|||If I understand your question correctly then you're phone is "pay is you go" or something to that nature. In that case, once you've run out of credit / have no more money on your phone you cannot sent text messages anymore. This would be why the message went to your outbox. Your sim card is fine and once you top up your balance you should be able to send texts again.