Yes, you're fine to bend over, in fact you should try to be a bit active. I was recommended to take a short walk (15-30 minutes) each day. I know it feels scary, but staying on the sofa and not moving could be worse for you, as a good strong blood flow is important.
Good luck! I had 2 embryos transferred 6 years ago and got my bfp on Christmas Eve. They are now boisterous 5yo twins tearing round the house in pre-Christmas excitement
Like Ophelia I was told to keep active, and walked a lot in the days after ET. I also kept cycling (despite my MIL's vocal concerns!), and my midwives reassured me that it was safe as long as I was very careful not to fall (I only cycled on separate cycle paths away from traffic). Not saying you should take up hiking and biking, but certainly bending over and light strolls are good.
Of course if you only feel like lazing on the sofa watching Christmas telly I wouldn't feel too guilty about it either, but I don't think we need to be as cautious as we think.