Question [Q] Stuck in "Safe mode"


So I switched batteries in my S4 (Android 4.3) and for some reason the phone now boots in "Safe Mode". All of my downloaded apps are unavailable to me and I can't get it to start up normally. I have tried taking out the battery for a while, rebooting with the volume down button pressed in and various combinations of this, which is what I have found in the suggestions on the Net, but to no avail. I'm getting pretty desperate here as there are a number of apps that I use in work which are now unavailable.

Does anyone know what I should do to get back to normal???

Grateful for any help/M
So far:
Palms > iPAQs > Blue Angel > Universal > Hermes > Kaiser > Rhodium > Xperia X10i > X10 Mini > X10 Mini Pro > X10i > Xperia Arc > toggling between Galaxy Nexus - Xperia Arc S - iPhone 3S - Nokia Lumia 800