My electric bill is oddly high?

My bill last month cost me $200, which is kind of high, but I figured it's just because the apartments is old, so the AC/heater unit uses a bunch of electric...that and the appliances are cheap and use a bunch as well I'm sure. It's been floating around that range. I got the bill this month, and it says we owe $390 for the month of December. Now... we haven't used any more electricity than last month, and I'm sure of this because we have even been trying to conserve to save some money. We've been turning everything off when we don't use it, and have been trying to avoid using the heater. We've called the electric company to have them come out and do a reread, which is going to cost us $8, but the meter might say the same thing. The only thing I can think of is that they've been doing repairs in the apartment next door. The lady had to move out because of plumbing issues, and I know they've had to knock out some of her drywall to check for mold, and also doing other various repairs. It is possible that her apartment's electric is being charged this way? And what should I do? I know there's no way we owe so much and having us pay that amount is really unfair. Is there someone we can call other than the electric company ( who isn't very helpful). Thanks for any help.