Bad afternoon run

This morning woke up with stomach problems so opted for sleep in, in the afternoon at 5:45 p.m. I decided to go out for my 8.5k run, I had a tempo planned for today, but I dont like to run in the afternoon, let alone do a workout! I felt ready to go, ate pasta at lunch, slept some, but as soon as I went out felt bad, was huffing and puffing, was hoping to feel better after 20 mins, but in fact felt weaker and was desperate to get it done, so I opted for cutting it short and call it a day after 5.5k in 32:23, never looked at the watch! I dont know what went wrong, but I felt very angry, I look at the bus station mirrors and my body is not even close to how it was, dont have the athlete body that I used to have, that upsets me a lot! at least I can run! Did I say that I hate afternoon running compared to what I feel in the morning runs, yesterday felt great and effortless, today felt like a race and it was much shorter run, oh well!!