Got offered a full time position, but I'm not sure if I should take it?

So currently I'm a contractor, and the company I worked for offered me a full time position. However, I believe they just made this decision blindly because they're anticipating a lot of the senior engineer leaving and that they need more body in the organization. The thing is, I'm kind of a shit developer. As I'm writing this right now, I'm struggling to write a unit test regarding someone else's chnages that was assigned to me. The lead has stated the task is very simple, yet I have no clue what I'm doing. I've been here 10 months, and it feels like I have not made any progress whatsoever. I should also note that during all of my time I have been moved from team to team for a total of 3 times.

Part of me knows that the economy is bad and you have to take what you can get. The other part of me just dread coming to work because none of this stuff is clicking for me at all. Need some advice on what to do next.