Car aggravation

A couple weeks ago we noticed my car would struggle to start a little bit. So we decided to take it in to the shop and have it checked. They took out this alarm system that they said was messing up my ignition. First of all, I didn't think I had an security system put in after the car was sold. Secondly, I don't know why that would suddenly happen now. I've had this car for a long time. But anyway, we took the car home. And now, this past week, it really doesn't like to start. It usually doesn't start the first or second time we try it. I had to drive Rob to work today because he couldn't get my car to start in the morning. Ugh. So now we have to take it back to the shop and see what is really wrong with it. I hope its just a simple thing like a battery problem.