teething and low milk intake

My son turned 7 months and he is teething. His 2 teeth just popped out of gum a lill and the other is about to. He is crying a lot lately and not even taking enough of formula. He used to take 7 oz every 4-5 hours but now only 2,3 oz . And cries almost all day. I don't know what should I do. Any suggestions? Also I feel like his legs aches. Every time I massage he feels relieved