Does my dads girlfriend dislike me?

I first met my dads girlfriend like five months ago and we got along just fine. we used to joke around i used mess around with her three kids and all that, she was a real nice person and she helped me on certain things and i thank her for that but around february she started to change. she would always watch me when i walk around to see if im sagging my jeans ( since my jeans tend to sag alittle) and she would look at me with disgust and she has had altercations with my mom a few times ( since my mom is a jealous b*tch) and i wonder if she dislikes me because of that. 8 visit my father everyday because i been dealing with self esteem issues lately ( which is weird because i always had fun) and i think she may be tired of seeing me all the time and the other day she was talking to my dad critisizing me about how i dont respect him when i do and that i shouldnt be having tattoos if i was to be his son and i felt really hurt but what do you guys think?