Don't let them push on your knee. You're just over 5 weeks, it'll come, but not overnight. When you're relaxing at home let your leg bridge between the chair you're sitting in and an ottoman or other seat. It wit happen immediately, but it'll happen.
True story...my dad, BFF and I all went to the same pt group, but they had their knees done before me. Both said the pt pushed on their knees, causing unbearable pain. I watched the pt with hawk eyes, just waiting for her to push down because I was not letting it happen to me. Apparently, my infection came before she had a chance to do damage, then I changed pt groups where no one pushed or pulled my knee, everything was done under my own power.
Give that extension time, let gravity do the job.