The OP asked about theft. And yes, suppose property/financial advantage by deception is possible though not sure where the deception is in the limited information we have.
re: Theft. No, didn't forget about dishonesty. OP said he had money trouble and he took money from work (this implies without permission, without a belief he was entitled to the money, and it was from someone he knew). Under these circumstances the provisions in s73 are unlikely to help. Real question is can a good lawyer twist any extra facts to construe a meaning that fits within s73. It is possible, as we don't have all the facts.
And who knows, maybe the boss is an understanding and forgiving type of person and will give the OP a second chance. Not every illegal act gets reported to the authorities.