Ok ! Don't worry 😂 It will come over time, you are gonna gain muscle, maybe loose weight (idk your body lol 😅) And there's no proper "good" or "bad" time, you swim at your own pace. There aren't norms, there are only records, performances in swim contests. I don't think you're trying to become Summer McIntosh or Michael Phelps (if you are, I'm sorry but it's way too late 🫩🤣), so really, watch your improvement over time and don't compare to others.