To continue or not?

I am not sure what to do about this whole couch to 5k thing. I am in week 5 but it has been three days since my last workout. It seems like whenever I get great momentum and start doing really well, something happens to throw me off.

During my first week 4 attempt, I hurt my hamstring really bad and took off 6 days so I repeated week 4. Now I am on the second workout of week 5 and have to run 8 minutes, walk 5 then run 8 again. This would be the first time I have run 8 minutes straight if I am able to do it.

I need to go workout right now but am trying to decide if I think I can continue this. I don't want to give up but the problem is, I just don't know if I am physically able to do this because I am overweight right now. It is a lot harder to run with extra weight on your body than if you are a normal weight or at least close to normal. I am not trying to make excuses but I am trying to be realistic about what my body can do.

I didn't start doing this workout plan to lose weight (although I need to badly) but I did it to prove to myself I can and to get my heart in better shape and also make a habit of working out. I know I have to eat a lot better to lose more weight but I thought this would move me in that direction. I haven't really been eating well so far in this plan so I wonder if that actually is making it harder on me.

I think for now, I am just going to keep trying and see how it goes. If I fail at my workout today (as in - not running the whole 8 minutes) I think I will just redo this workout in two days. I really want to get through this whole plan but that would mean in less than 4 weeks, I would be running 30 minutes without stopping. I just don't see that happening, but I guess I will have to wait and see.