We don't know what will be the price of bitcoins after halving because now is not the same before. That investor is easly believe in hype that bitcoin will increase because of Bitcoin Halving, Bitcoin will increase upto 1 million and many more speculation that in the end are not come true.
Investors now are very smart on this , thats why price of bitcoin after halving will not be really increases futher and breaks the record of all time high in 2017. Now many investors much focus on securing thier profit and this wil prevent bitcoin to increase futher after bitcoin halving.