Congrats sa 15 weeks, mama! Yes, normal yan, a lot of us felt that stretching, bruised feeling as the uterus grows, parang muscle soreness lang from the inside kaya nakakabugbug talaga. But since you're describing it specific like nabugbug and walang ubo, best to mention it to your OB next visit just to be sure everything's good, lalo na if it gets worse or may ibang signs, peace of mind lang talaga, at least alam mo na all's well with baby.