HELP!!!! Rookie Mistake! INVERTOR FRIED?

Hey everyone. Any help would be greatly appreciated.

So I bought a used 2011 Prius. My automatic locks were not working, so I decided last night to swap out the battery. It was night time so I couldn't see exactly the positive and negative terminals. Well, I reversed them as I was trying to put the new battery in...My rear lights beeped and flashed once, saw sparks and smoke. Then I stopped there and put the old battery on correctly and tried starting the car. The dome light works as well as the headlights, but they seem dim. However, the car will not start. It shows the engine sign and then the power button just stays orange and flashes. Then I press the power button again and it shows the yellow triangle and tells me to depress the brake and press the power button. I have checked all the small fuses in the engine and under in the car and they all are fine, but the 12v battery fuse is not broken, just discolored. Could I have gotten lucky and it is not the inverter? Should I try to put in a new 12v and 12v battery fuse? How likely is it that I need to do a $3,000 repair? I just got the recall for the software from Toyota a few days ago too. Help is greatly appreciated!

Thanks! By the way, these forums are a lifesaver! I also spelled inverter wrong. Oops.

 

Just a visual check to see that they were not broken.

 

Knowing Toyota would probably charge me $10,000 to get it looked at, I am going to have someone come on Monday to test the 12v battery fuse with a multi meter. Fingers crossed.

Fingers crossed! I am fine with car repairs, just not ones that I create for stupidity.