Last week my alternator and battery went. After having them changed the check engine light wouldn't clear and I needed to change the 02 sensor, mass airflow sensor...done. Then the shop wanted to charge me an arm and a leg to change both camshaft position sensors, so I brought it home and had a friend change them. When I drive it off the lot, the battery light came on. My friend had a hard time actually finding camshaft position sensors, but then finally did after awhile. He changed them out, but now the D is blinking AND the battery light is still on after a minute of start up. To make things worse, the car doesn't stay up right away like it used to. It hesitates a bit. I had absolutely no problems with it before this and I can't believe how many things just went at once. I haven't driven the car now. I'm scared to. I don't want something worse to happen. Someone, please help! What do I do?!