New brake pads - uneven wear?

[RobBMW]

Changed the front pads on my daily Volvo V70 at the weekend.
Once finished I took it for a drive and had hardly any braking under the pedal as it almost went to the floor. Bled the system and this improved greatly, still felt a little spongy though but put this down to the new pads perhaps needing bedding in.

Anyway, 24hrs later and I've done about 50miles of driving and noticed that the inner section of the brake discs (at the front) is staying rusty, suggesting the pads are only wearing on the outer half of the discs.
I presume this would be why the pedal still feels a bit soft?

Is this normal for new pads? do i need more bedding in time? Bear in mind they're being used on the existing discs?

Had enough trouble with this car recently and sick of having to take it to garages to do things on it that I can't do at home. I thought changing brake pads would be easy enough apparently not

[RobBMW]

Thanks everyone.
I got air in the system as I was advised to open the bleed valves when pushing the pistons back to accommodate the new pads. Apparently not doing this can cause some issues of seals failings in the master cylinder which I didn't want.
Sort of wish I'd ignored that advise and risked it after the issues I had.

Anyway, that was my plan, give the pads a few hundred miles/couple of weeks to line up with the discs. If not, I'll take it apart again...