Annoyed

I went out for what should have been a two and a half hour bike ride today. I did just over the hour and had to stop. My back hurt so much.
I went to spin last night and as we haven’t got a class next week our coach decided to give us the mother of all sessions. OMG it was so hard. I could feel my back starting to hurt. Today I paid for it. I shouldn’t have put so many gears on knowing I was heading out today. Like an idiot I did. No boxing tonight either.
I think I’ll have a day off tomorrow from activity or just go for a gentle swim.
I’ve got 8 weeks to be able to swim 1.2 miles...that’s ok. Then ride 56 miles followed by a half marathon. I have a cut off time of 8.5 hours.
At the moment my furthest bike ride is 27 miles and my furthest run is 6.5 miles. I’ve got an awful lot of hard work to do. I’m not helped by going away twice during those 8 weeks either. To say I’m worried is an understatement. I wish I had an extra couple of months to get myself fit. So bad back you need to go....please.