Sounds like DOMS (delayed onset muscle soreness).
"Delayed Onset Muscle Soreness - Definition
Delayed onset muscle soreness (DOMS) describes a phenomenon of muscle pain and soreness that is felt 12-48 hours following exercise, particularly at the beginning of a new an exercise program, after a change in sports activities, or after a dramatic increase in the duration or intensity of exercise. This soreness is a normal response to unusual exertion and is part of an adaptation process that leads to greater stamina and strength as the muscles recover and build. The soreness is generally at its worst within the first 2 days following the activity and subsides over the next few days."
Taken from this site....
http://sportsmedicine.about.com/cs/injuries/a/doms.htm
After the first session on the well known '100 press ups' plan i couldnt move my arms for 4 days :*text deleted*: so I wouldnt worry too much
Do what I did-Give it another days rest and try some light work on your affected areas (worked for me) and take it from there,or if problems persist consult further guidance from a GP or physio