It is hard especially when you know what to expect and that is not happening…. You have every right be concerned…. Reach out to Dr have that conversation let him explain why two recovery are different ….maybe in doing so he can put your mind at ease… I know won’t solve things but sometimes just having information we need helps our psyche….sounds like you did very well your last tkr ….. so you know it does get better just takes little longer sometimes…..when I had my tkr I could not sleep pain , insomnia I tried olly gummy… I took these for like a month or two label said you can take two but I only ever needed 1 that is what I started at helped tremendously…….having a good night sleep helps you get through the tuff days …. I doubt if you are allergic to anything they used hence you did not have reaction with you last tkr ….just keep pushing through this time is harder just push harder ….unfortunately you have to dig down dip you got this , having knee replacement is not for lazy people that’s for sure …. Call the Dr that may hopefully give you piece of mind ….