Not going well

This pictures sorta sums it all up. I just am not doing well with running lately. I dont get how someone can run a half marathon, a ten miler, a 6 miler, and a 5K and still not be able to do it. I was supposed to run 4 miles on Thus and made it probably a half mile down the road and had to turn back due to low blood sugar issues. Then I was to run 7 miles on Sunday and made it about 1 and then quit on Mike. Its just not going well. I am getting cramps I havent had before and I feel worn out all the time. I just really dont feel like I can do it, or even halfway do it. We'll see what happens. Mike is going to re-do my training plan and make some changes. I am just worried that I cant get back to the running regime I was once accustomed to. I feel that I have failed myself and Mike and am just not meant to do this running stuff. Hopefully this is just a setback and it will pick up again soon and the Richmond race will go well. I am just not feeling confident about this lately.