Help needed!!

[Kitson93]

So today after work my car wouldn't start. Flat battery I assume.
But when I drive slow then change from 1st to 2nd the dipped lights appear to get dimmer then brighten up. Is that due to low revs or the alternator.
Car: 1.2 16V 2003

any help is greatly appreciated!

 

[Kitson93]

Got it sorted!