Help! - Red Triangle with P0A40 and P0A41 Codes

Tonight, son used my 08 Prius and inform me that the red triangle warning appeared on his way driving back.
I tested driving the car by myself with the red triangle warning on for 3 miles, without feeling any difference, After the test drove, I turned the car off and went to find the OBD II scanner. After I plug the scanner in then turned the car on again, the red triangle warning didn't come up at all (am I too lucky??). Anyway, the engine check light still on and the scanner found the codes are P0A40 and P0A41. I erased the codes with scanner and test-drove the car for another 2 miles and no red triangle or engine warning light coming on and the car drove like normal.

The only I did to the car was replacing the headlight bulbs with LED bulbs bought from Ebay that made by Autofeel one week ago. The bulbs replacement was very difficult so I had to take the entire headlight assemble out then put them back. I didn't aware that I damaged anything.

Need your help to share your opinion what could be root cause for this red triangle warning and codes. Thanks.

 

In summary, I experienced:
1. A red triangle warning on then disappeared by itself.
2. Engine code P0A40 and P0A41 were found by the scanner.
3. Car was derivable without any difference (my feeling)

My Questions are (need the help):
1. Is this the hybrid battary problem or other kinds?
2. How expensive could it be for fixing?
3. Is this possible to fix by DIY?
3. Can I still drive the car if the car has no noticeable problem?