Checking my design for a portable cell phone charger

[geniass]

Hi all,
So I've been designing a rechargeable portable cell phone charger (or powerbank or something) that uses a lithium-ion battery to charge a phone. Here's the schematic:

I got the circuit board made on a milling machine but it's double sided so the homemade vias are not great. Anyway when I connect the battery to the circuit (battery is JP3 in the schematic) LED1 switches on (which is not supposed to happen) and the battery makes a suspicious hissing noise. I haven't left it connected long enough to find out whether it explodes or not.
I just want to confirm that my design is correct or if I've made some error.
VINA, VIN_USB and JP2 in the schematic belong to this USB power multiplexer: http://www.pololu.com/product/2594/specs. It just switches between USB power from the usb charger and power from the battery.
The step up converter to get 5V out of the battery is this: http://www.pololu.com/product/798 and the charge controller is a MAX1811. The transistor circuit in the bottom-right corner switches the MAX1811 between high and low charge current.
Thanks in advance

[Alex Eisenhut]

I don't want to stop your fun, but

http://www.ebay.com/itm/Luxury-Portable-5600mAh-Battery-Backup-Power-Bank-USB-Charger-External-for-Phone-/301265152780?pt=US_Cell_Phone_PDA_Chargers&var=&hash=item4624cd6b0c

Is it really worth the time and effort and resources?

[geniass]

I know they exist, but honestly it was just to learn something about designing basic PCBs, and it's basically cost me nothing so far (I can get the components and PCB through my university at low cost). Anyway buying stuff through ebay is risky since our postal service is currently not functional.