HSG may cause pain lower abdomen but you have not mentioned the month in which the procedure was done.Premarin is a conjugated estrogen so it is better to take evadiol which contains estradiol valerate
.Estrogens are taken from 6th to 9th day of the cycle along with clomiphene
citrate which is given from second to 6th day of the cycle.You can take tablet meftal spas
for the cramps and thigh pain under doctor's prescription.Get proper investigations done for the infertility treatment
like FSH , LH , Estradiol , Progesterone
, prolactin , Thyroid profile and follicular studies etc.
Best wishes and good luck