I don't agree that its harmful to skip a meal or that your metabolism slows down from one skipped meal. Its more from an extended period of eating severely below your daily calorie needs. Actually I think skipping meals could be used as a good way to lose or maintain weight. If you overeat one meal or even for a whole day, you're more full later on so you might not need that meal. I feel total overall calories for the whole day is what counts (though sometimes people get overly hungry from skipping a meal and then binge later, which we dont want to happen either).
I also question whether you would be able to maintain 155 at 5'5" and actually be normally eating 4000 calories a day. It seems like you wouldve ended up a lot larger, but then again you're very young and growing so what do I really know. It just raised a little flag that didn't quite sound right (and I could easily be wrong as I'm no expert on this).
Its impossible to help you when you list your meals as "a good meal for bfast", "a good meal for lunch". That tells us very little.
Punching exercises with 20 lbs doesn't sound so great either. I would do compound exercises that work your large muscle groups to burn calories. Like squats, lunges (with or without the dumbbells) and chest and back exercises if you have access to equipment.
Also, try interval training like walking, then jogging, then slow walking for 1 to 5 minutes, then sprinting as fast as you possibly can for 20 seconds, then slow walking again, more sprinting for 20 seconds (that's the part that really gets your metabolism going), then slow walking, then end it with more jogging or fast walking.
I feel with your stats that you're not going to lose 10 or more lbs per month unless you starve yourself, which has really bad effects on your metabolism and body and is not recommended. Slow down. Smell the roses. Enjoy life chubby or not, and soon enough you'll be where you want to be. Slow and steady wins the race (and lots of patience).
Two things you're doing right are that you're trying to learn how to count calories and learn how many calories actually are in what you're eating (and some of it is very surprising as you saw), and also that you're not trying to starve yourself to get the weight off quickly. Its not worth slowing your metabolism down that way.