Hi gmb_sim
Different surgeons have different protocols following ACL surgery. If your surgeon and physio have told you that you are able to full weight bear (FWB), then the graft is well fixated and stable enough for you to FWB. This doesn't necessarily mean that you WILL be able to do this. You need to progress your weight bearing as your pain allows - you can expect to be on crutches for 2 -4 weeks. You may have been trying to take extra weight on the leg as you felt this was expected of you, this may be the reason that the knee has now swollen up so much. You should consult your GP if the swelling and pain is really excessive and not within "normal/expected" limits. Ice and elevating your knee should help to reduce the pain and swellling. The exercises that you are doing are great, don't worry about adding any others until you see a physiotherapist who will progress your exercises as appropriate.
Hope this helps!
Emily