Changes made to contract without my initials/signature?

[Mikey L.]

We signed a contract to buy a house at the lawyer's office. A few days later, the lawyer made manual handwritten changes to the terms of the contract (number of days we are allowed to get loan and mortgage changes - down payment amount increased and type of loan changed). We were never asked to sign the changed contract or even initial next to the changes. The lawyer did email the changed contract to my husband and asked to confirm receipt but my husband never checked that email and never confirmed receipt. However, the lawyer called my husband right after sending it and said that the seller wants us to make those changes and supposedly my husband said "ok" over the phone. I was never aware of this and my husband did not realize the contract was changed since we always thought for that to happen we need to sign or at least initial an actual piece of paper or send something, anything in writing. 

Are we bound by this new terms on the contract? Can it be voided and only the original terms of the contract stand? Is the only way to fix this by getting a new lawyer? Would we sue the current lawyer for changing the contract without our approval? We only have 15 more days to secure a mortgage, after that we lose our escrow so I dont know if it even makes sense..