Pain in lower left abdomen among other things...

I have a distinct, rather sharp pain in my LEFT abdomen near the bottom. Thoughts? It is worse when I bend over. First noticed while descending a hill on my road bike. Thought I may have pulled a small muscle as I had just had a brutal long climb. That was a couple of days ago. Didn't feel it again until today. I had an apple juice fast...so I am thinking it may be gas and colon related.

I am full of toxins! So much so that I could not get more than one day of my fast done without the most brutal headache I have had in years and a feeling a nausea. My skin is starting to take matters into its own hands and breaking out in eczema as my liver etc must be at max saturation. What should I do first?

I HAVE started to increase my water intake to a full gallon a day (I am 220 and active on the bike on a daily basis, but been doing mostly hard work and thus not much fat burning), since I feel that I probably have been dehydrated for years.

My diet is getting cleaned up as well, but I need your advice on which foods do the best cleansing at the moment since I can't seem to fast well yet. Then hopefully I can start incorporating some short fasts and then finally do some actual cleanses.

Thanks for your help.