Overall your swing looks pretty good. There are just a couple of things to work on to elminate some of the miss hits you are describing.

First take a look at these two images, you and an un-named PGA Tour player. Notice the difference in arm position. You looked like you’re forcing your arms too close together. Your elbows look like they are almost touching. Your shoulders are too wide to be in this position naturally. Notice the other player, his arms look more relaxed and in a natural hanging position. Try to get a little more space between your arms at address.

Next, at the top of your swing it looks like your left shoulder is pushing your head back a little. Maybe your shoulder isn’t going down under your chin enough? Or you are trying to turn a little to far back. Either way, try to keep your chin down like you have it at address. See the tour players head, basically it’s in the same position as at address, his shoulder has moved under his chin, not into his chin.

Remember me telling you how every player has their own errors that they will tend to fall back too? Well take a look at your left foot on the downswing. It’s moving a little too much. The heal looks a little raised and to much weight is on the outside of your foot early in the downswing. Remember when you used to do that when you were younger? Well you’re not doing it as much as back then but there is still more movement than we want. Work on keeping your left foot planted in one spot until well into the finish. See the difference in the two images below.

At impact you can really see a difference in foot position. Your left foot has rolled to the outside to soon. As a result you can see how your left leg is slightly bent and your knee is moving towards the target and past your foot. When you were hitting it very solid your impact position was much more like the player below. Work on getting your knee over your firm, planted foot, not out towards the target.

Finally the finish. If you get those parts above better you will get into a better finish where you are over your left leg a little better, right now you have a slight lean back position. Again, when you were swinging really good you looked more like the PGA Tour player.

These are kind of picky issues but they are big influences on miss-hits and falling forward like you’ve been describing. And of course you don’t have to swing EXACTLY like this player but he is a good example of positions that really good ball strikers attain during their swings. So I think you should work to get as close to these as possible. But like I’ve said, when you were hitting it really good, this what you were doing so you shouldn’t have any problem getting back into this spots.

Let me know if this helps or if you need more info.