I see this common mistake often. Here’s a little bit of help to clear things up.

Sense is a verb meaning “feel” or a noun meaning “intelligence”. It can often refer to the five senses or the different forms of perception, reasoning, and understanding.

Since is most commonly an adverb often referencing time but can also be used as a preposition or as a conjunction. It is used to express something that occurred previously but whose effects continue to the present.