Hello, Mikey - and welcome to the forum.
First thing I have to point out to you is that out of the THOUSANDS of people who have THRs done, very, very few need to seek out fora like these for help and encouragement because, quite simply, they don't need to. Their op and recovery go swiftly and simply and they are back to a 'normal' life very quickly. Also it is often a trick of the mind to 'see' only those negative posts and miss the ones that have positive stories.
I have two friends who have had THRs, one was a conventional approach two years ago, the other MIS last summer. Neither seemed to have any problems, took their post op period in their stride and are back to normal in no time. Sites like this are self selecting meaning that generally only people with problems will go looking for them. Or people like yourself who are anxious and seeking reassurance.
So, let me address the problems you have given as best I can.
First off, everyone is anxious-terrified about having operations. This is not a failing or a weakness on your part. It's human nature. It's a bit deal to be putting yourself in the hands of total strangers, some of whom you won't even set eyes on. I've worked in operating theatres all my professional life and I have had operations major and minor. I was anxious every time and often I knew the people behind the scenes who would be looking after me!
Second, your PA was quite correct. 2-3 days in hospital and a short period of taking it easy would be about right. The good thing about minimally invasive surgery is that the major muscles and ligaments are not divided - this is what makes the recovery more protracted and difficult. So you won't have that bit. And once you have had one done, the second should be - well, not exactly a breeze, but certainly much, much easier.
Finally, I would like to ask if you have confidence in your surgeon. Did he spend time with you? Were things explained to your satisfaction? You said he's done thousands - that sounds pretty good to me. I'd always want someone who had a good track record.
If there are any specific questions, do feel free to come back and ask. That's what we are here for. I check this site at least once and sometimes 2-3 times a day so you can be sure of a reasonable quick answer.