Is it permissible to perform tayammum due to fear of a surgical wound becoming inflamed when performing ghusl after menstruation?

What you did is incorrect. It is obligatory for you to wash what you are able to wash of your body, and to perform tayammum for what you are unable to wash. If you neglected what was obligatory upon you, which is washing what you were able to wash, then you must repeat those prayers you performed.