You have the battery in while plugging in and taking it out? See any magic blue electrical sparks? If so, then probably. Always remove 1 terminal from the battery. It takes a second and it prevents this.
Other than that if nothing has changed, perhaps your battery is too low. Do you have a deep cycle or regular crap walmart battery? I just yesterday got back from vacation and put my deep cycle battery back in. It took a second to crank it instead of the normal turn and vroom. It was turn crank crank crank vroom. And that was only a week and a bit.
So drive around a while, recharge it to full and see if it helps.