Hi and Welcome to the forum!
If she is indeed a purebred Mini Lop I do belive she is over weight I think per ARBA (American Rabbit Breeders Assoc) there top weight is 6.5lb so if she is 6.18lbs she is infact 7.02lbs (Is that right

I am not a math person) so she is overweight. If you want a critique of her type post a picture of her in the critique section of the forum and other mini lop breeders will tell you what they think of her but do try and pose her per the breed standard to get the best critique.
Once again Welcome to RH the best Rabbit forum!