Okay. No I don’t think it’s an issue. More likely it’s you remembering that in the past you’ve always regained any weight loss, so here you are losing weight again and you think, “this won’t last” because it never has before. Very understandable.
I suggest that whenever you become aware of this “it won’t last” fear, that you bring yourself into the present time and remember, “so far, so good… let’s see what happens.”
The fear is about the future – which hasn’t happened yet, and you don’t need to know how things will turn out. So be willing to not know. Right now, you’re doing fine.
In addition, keep your non-weight benefits firmly in mind and take the position that these will motivate you to continue to eat less no matter what your size.