Hi CB
You may need a cup of bouilon. You have been parting with a lot of water and it most likely has your electrolyte balance off a bit. It can may you feel a little edgy or jittery. Have a cup of plain old bouilon or a "fast soup" they are enriched with potassium and generally help too. The coffee is fine -- but mopst likely won't help the jitters. You are doing great. Just keep it up.
jan