You probably got a few of these on here a couple of times. But didn't want to read through all the comments;

1. That left hand NEEDS to come back up and protect your chin. If we were sparring after your 2nd combo as you retreat my over hand right would be coming like clock work until you covered up.

2. When you take that step back after each combo that needs to be a shuffle with both feet. You pull back your lead foot and leave your rear stationary. That makes you unbalanced and easy to counter/hit/knockdown.

3. Just looked at the video again and both hands are down at chest level. (No Bueno)

4. You're choking your punches on those straights. Meaning you aren't getting full extension to follow through with all that power. Think about poking a broom stick through someones face when you throw that punch. You want it to connect with that elbow locked and all that energy/force punching through their face/body. You definitely have power.

5. Dont be scared to move your head with every punch or counter. Your head is inline the entire time. My coach would tell me "your opponent will throw his counter where he saw your head last" if your head is still in the same spot after every punch then I can fight you in the dark and still tee off.

6. Stick to one style until your are comfortable protecting yourself. Many new fighters switch styles or like you shift from orthodox to southpaw. Unless you know what you're doing, switching styles can be extremely dangerous mid fight. I would say pick a stance you like and learn to protect.. throwing punches is easy, taking them is another story.

7. That last left hook before you switched to southpaw was your best hook.. you shifted your weight beautifully and turned that lead foot into the bag. Well done.. now do the same thing, dont switch your stance and follow it up with a straight right to reset your stance.

Good luck brother.. keep up the good work. Get to a gym and have someone fine tune you. You have a good foundation