I live in a cold climate where freezing temperatures begin in September. I had replaced the battery in my car then, a little more than 2 months ago. I had also added a new front and rear dashcam to my car. My battery had some how drained very quickly and I don’t know how. Yesterday, as I was driving on the highway the battery light came on but I continued driving for an hour. Shortly after the RPMs went of control (the needle kept going up and down very fast) and my speed dropped and I was barley accelerating. I stopped on the hard shoulder before I got towed for free.

Any Ideas?