Nice little trade you made there, however let me give you a hint:
You use options for directional trading, so you play for gamma.
Instead of buying dailies have a look at the vol surface first.
Term structure is downward sloping, meaning short term is cheaper than long term. Historical vol is 135 for the 20 average, JUL9 trades at 146, JUL16 at 165.
Short term vol is coming down hard from over 400.
The better trade IMHO would have been to sell 16JUL 51 puts and buy 9JUL 51 puts for a structure like this:
You are long gamma and short vol, but still pay decay. The advantage over outright straddles is the fact that you have cushion in case the move gets stuck and vol collapses AND you can trade these for real size with a single combo order for way less edge loss against the MM. 9JUL does 300k a day so you can easily throw 1000 spreads at it with a single order.
Collect profits by either getting rid of the extra puts or keep full size and buy back the delta via shares.
Straddles or outright puts are actually pretty mediocre choice here, because the weekly straddle implies a daily move of 6% whereas the actual move was 4% on July 1st. That should already give you a hint that you're overpaying as you are fighting a 2% risk premium.
In addition you have pretty insane skew risk here:
If you are wrong, you lose on delta/gamma and vol as your strike slides down the skew.
The calendar would also help against that.