Battery draining abnormally fast

Started driving this morning from Murfreesboro, Arkansas to Santa Fe, New Mexico, everything was fine until the last 200 miles or so. I had some music on and the ac and thought that was draining the battery, turned everything off but then the battery wouldn't gain energy like it normally would. Accelerating would drop the power bar very quickly, and it would go down to one or two bars from accelerating up a small hill on the highway. I was able to milk it all the way to Santa Fe thanks to the hilly nature of the area but I'm concerned about the discharge rate and I'm not sure if I'll make it up I-25 with the elevation gain. I did check the oil a ways back and thought it was low so I topped it off. I've also driven around 2000 miles since Monday with a bunch of stuff in the car as I'm in the process of moving to boulder, Colorado. It's a 2004 gen 2 Prius, 12v battery is 6 months old but the car did sit for almost 3 months and had to be jumped a few times initially. Any ideas on what the problem may be? There's no dashboard lights on but the maintenance required one comes on for a second when I start it now, then goes away.

 

Sorry haha I'm using my phone sitting in a hotel, definitely going to get in touch with Boulder hybrid. The battery is the original and the car sat for so long because my mother( whom I bought it off of) went to Germany for a while and when she got home then had to get open heart surgery for a congenital heart valve problem. Her boyfriend failed to maintain it as he was supposed to. I'll try the discharge test in the AM and probably bring it somewhere local. Otherwise I'm probably going to see how far north I can make it and just have a friend with a truck tow the rest of the way. I'm thinking the hv is going, Boulder hybrid does battery recondonditioning right?

 

Thanks! I don't see a link in your post btw could you post it again?