Where exactly did it spark?
Which fuses are blown?
It sounds like you have a wire shorting out somewhere. Brake lights and headlights should be in separate circuits. If both of those fuses are blowing then you need to chase the wiring after the box.
Check the box to find out which side of the fuse has power coming in and which side goes out to the lights. Once you do that, check for a direct short to ground between the fuse connection going out and a chassis ground. If you have a short look for bare or damaged wires. You can move the harness around to see if the short goes away as the wires move.

A bad turn signal switch could cause the problem too. The brake lights and front side markers are joined at the turn signal switch. If it shorts out it can blow both fuses. The headlights are on the same fuse as the side markers.
I don't think the lights will work if the switch is unplugged. You can unplug the flasher and see if the brake lights still work after replacing the fuse.