9 week old sleep problems?

Lindsay
Three nights ago, my 9-week old started waking every 1.5-2hrs at night. Our earlier solutions for sleep - baby-wearing, nursing, rocking - and his longer sleep "patterns" have suddenly disappeared.  He won't sleep in crib for longer than a few minutes, nor will he co-sleep adjacent to us in bed - now must be held while sleeping, usually by me or he screams his head off. Husband and I are reaching our breaking points.
Anyone else dealt with a sudden change like this? Mom and MIL keep suggesting formula supplementation but I'm not sure that would help get him to sleep in his crib again (though at least it could give my husband a way to soothe the baby and let me at least get a 3-hr stretch between breastfeeding). Thoughts?