Welcome to Android Central! What tablet do you have? I'm assuming its charging port isn't the standard microUSB port, if you were able to fit your house phone's charger in there. It sounds like one of those DC power ports. The problem is that there is fairly wide variability in voltage and amperage for those kinds of chargers, so you can't necessarily interchange them. It's possible it might have damaged the device, but it's also possible it didn't charge it at all overnight, and the battery died.
Charge the tablet with the original charger, and let it sit on the wall outlet for a good 6-8 hrs. Then try to power it on again.