After Dr. Frankenstein had finally creation he starts of by saying ‘His limbs were in proportion, and I had selected his features as beautiful. Beautiful!’, but after he takes a good look of  what he calls a ‘monster’ he says: ‘Great God! His yellow skin scarcely covered the work of muscles and arteries beneath; his hair was of a lustrous black, and owing; his teeth of a pearly whiteness; but these luxuriances only formed a more horrid contrast with his watery eyes, that seemed almost of the same colour as the dun-white sockets in which they were set, his shrivelled complexion and straight black lips.” and now keeps referring to it as a ‘the monster’, and the when the ‘monster’ is taking care of him the morning after he created it he refers it to the ‘miserable monster he had created‘ .  

I don’t think it was right for Frankenstein to react the way he did towards his creation, what I think he should’ve done was reacted in fright at first and then try and see if he could fix the ‘problems’ that he could see like the yellow skin, black lips etc.