Massallah pertaining to Umrah and Ihraam

Assa laa mu alaikum mufti
I would like to know if it is allowed to go from south africa to medina first when going for umrah, put the ihram on in medina and first go to all the recommended places in medina before you go to mecca to perform umrah. Will the umrah be accepted and will the reward be less for doing it in this manner.
Jazakala