Warning lights - What do they mean?

Hi there, and thanks in advance for any help anyone can offer.
I've got a 2007 Prius with just under 100,000km. This weekend, 4 warning lights came on - 3 on the dash, and 1 on the main interface. They are:

On the dash:
1. Large exclamation mark inside a triangle
2. Smaller exclamation mark inside brackets
3. Check engine symbol

On the interface:
4. A weird shaped orange tear drop with a vertical line through it.

I haven't drive it around, but it starts no problem. Interestingly, I hooked up a code-reader, got a green light from it, and a cryptic message. Specifically, the code reader displayed the following message: No Powertrain DTCs or Freeze Frame Data is presently stored in vehicle's computer.
I don't know what this message is, and feel no relief from it

Below are the pictures of the warning lights and code message.
Any help would be greatly appreciated!!

 

A bit more background info:
- I've never had any of these warnings before
- I just had an oil change, not sure if the system was reset to register the oil change

 

Hi guys - thanks very much for the feedback.
Prodigyplace - yes, the 12v battery is low, and I can't confirm if it's the original, but based on the kms being so low I would assume so. In the 'Vehicle Signal Check Mode', it says I'm running at 11.4-11.5v, which youtube says makes it in need of changing - Toyota dealer didnt make a big deal of this.

I took the car in to get hte codes read and was told that I needed a new Hybrid battery based on having the following to code: P3000 & P0A80. They explained that of the 18 cells, one is reading lower than the rest at 15.2V - apparently the differential between that one (cell 16) and hte others is really serious.
I asked if there was a connection between the low auxiliary battery and the current issues and was told no. I asked if the car would give me any warnings when the 12v was getting low and was told no. They were in agreement that all this seemed odd considering the low kms on the car (95k).

Interestingly, they offered to disconnect the main battery and leave it sitting overnight, then reconnect it in the morning...the mechanic said that this helps 'equalize' the cells, and swore that he'd seen positive results from this. I said this sounded very bandaid-ish, but as there was no charge for this, agreed to it.

They removed the warnings from the dash and drove the car out...so if you didnt know what was going on, you'd have no way of knowing. They told me there's no way of knowing how much hybrid battery i had left - could be days or months.

Not sure what to think and don't have much confidence, but below is an image of the diagnostic, and I'll follow up tomorrow with the 'equalizing' results. For the record, I was told that a new battery would be $2900 + 5hrs @$125 to install. Extremely unlikely that I'll put 4K into an 11yo car...even if it's only got 95km on it. Any comments or advice is more than welcome - thanks!!