I went to the gym yesterday for the first time in a while. i did 5 on recombit bike, 10 on tread mill and several lunges. the very next day i could hardly get out of bed. i have to ease into sitting. my thigh to my calf hurt. how can i get pass this?

Too much lactic acid was produced due to overdoing & deconditioning. Lactic acid will resolve by time, 1-2 days, but you can take Ibuprofen OTC 200 mg x 3 tablets with full stomach every 6-8 hours for 1-2 days so you can move around easier.

Using muscles "unused" for a while for strenuous activity which one's mind remembers from past workouts will produce discomfort as described. Anti-inflammatory medication such as ibuprofen will relieve some of the discomfort. Gradual introduction of increasing activity is recommended, with increases graded as to degree of "after workout discomfort" .