toss or keep, wwyd?

miniray

I pumped this morning so that my mom could give LO a bottle while DH and I went out to dinner. The milk was never frozen, I pumped this morning and stuck it in the fridge. My mom stuck it in a bowl of warm water to heat it up but LO didnt end up needing it (we got home and I just put him to the breast instead). I stuck the bottle back in the fridge. Is it safe for me to freeze it or should I toss it since its already been warmed once? WWYD?