if she complains of fatigue so often, you should rule out 2 thing first
trunkal obesity, tiredness
, easy fatiguability, lethargy
, excessive cold, dryness of skin etc are features of hypothyroidism and some many of these are common to anemia also.
pain in lower abdomen can be because of muscle pull or something like that your daughter will better appreciate.
UTI can also be a possibility as she complains of frequent urination
as well. frequent urination is not only a sign of diabetes
. and generallyy diabetes that is inherited from parents presents late.
obesity may also lead to early puberty that you say is already showing up in your daughter.
my opinion would be you should consult your pediatrician
for assessment in the line i suggested or what other things he may find suitable.