Too much? Tw: weight-related issues

Hello. I am wondering if I should lose weight. I am 5'6" and about 140lbs. Lately I've been getting bothered about my size and maybe I should make a change? What would be my ideal weight in your eyes? What's too heavy? I know my BMI is in the "healthy" range but I still feel like I'm fat. I do have bulkier breasts (38D) which make me feel really self conscious because whenever I wear pretty much anything I feel like I look heavy. I just don't want to live like this anymore.

Thanks for reading, commenting, whatever