Battery percentage decreasing while charging!

Question

Preface: Please forgive my technological ineptitude in advance. I am completely computer illiterate and have embarrasingly little tech vocabulary.
Okay. Help! While my MacBook Pro is plugged in and charging, the battery percentage is going DOWN instead of up. Yikes. If I stop using the computer, close it and let it charge, the battery percentage goes up when I check it after 20 minutes or so. As soon as I start using it while it's still plugged in however, the battery drains (goes down even though it's plugged in). I've pasted the System Report on Power below (I have no idea what any of it means), the recommendation was from another topic forum. Does anyone know what is happening w/ my laptop? It should also be noted that this is a brand new charger (60W MagSafe Power Adapter), but was still happening before with my old charger before it died (the magnetic piece detached from the part you plug into the computer). Also, it seems to be getting really hot (the new one AND old one!) Thank you for your help!!!
Battery Information:
  Model Information:
  Serial Number:          W0113445WD3BA
  Manufacturer:          SMP
  Device Name:          bq20z451
  Pack Lot Code:          0
  PCB Lot Code:          0
  Firmware Version:          201
  Hardware Revision:          000a
  Cell Revision:          158
  Charge Information:
  Charge Remaining (mAh):          4428
  Fully Charged:          No
  Charging:          Yes
  Full Charge Capacity (mAh):          5045
  Health Information:
  Cycle Count:          496
  Condition:          Normal
  Battery Installed:          Yes
  Amperage (mA):          -868
  Voltage (mV):          11995
System Power Settings:
  AC Power:
  System Sleep Timer (Minutes):          10
  Disk Sleep Timer (Minutes):          10
  Display Sleep Timer (Minutes):          10
  Wake on AC Change:          No
  Wake on Clamshell Open:          Yes
  Wake on LAN:          Yes
  Current Power Source:          Yes
  Display Sleep Uses Dim:          Yes
  PrioritizeNetworkReachabilityOverSleep:          0
  Standby Delay:          4200
  Standby Enabled:          0
  Battery Power:
  System Sleep Timer (Minutes):          10
  Disk Sleep Timer (Minutes):          10
  Display Sleep Timer (Minutes):          2
  Wake on AC Change:          No
  Wake on Clamshell Open:          Yes
  Display Sleep Uses Dim:          Yes
  Reduce Brightness:          Yes
  Standby Delay:          4200
  Standby Enabled:          0
Hardware Configuration:
  UPS Installed:          No
AC Charger Information:
  Connected:          Yes
  ID:          0x0100
  Wattage (W):          60
  Revision:          0x0000
  Family:          0x0085
  Serial Number:          0x009b16e5
  Charging:          Yes

Answer 1

Sofia925 wrote:
. As soon as I start using it while it's still plugged in however, the battery drains (goes down even though it's plugged in).
This is normal. When cpu/gpu intensive activities are run, sometimes computer
may draw power from the battery.
Try resetting SMC.
1. Reset SMC.     http://support.apple.com/kb/HT3964
    Choose the method for:
    "Resetting SMC on portables with a battery you should not remove on your own"
Best.