I've been on Apixaban for over a year now ,after having a pulmonary embolism. Can't be bothered to go downstairs to look at the box, bur I think I was on 5g twice a day until quite recently. My dose is now 2.5g twice a day.
I've had no side effects at all as far as I can tell!
One thing I've noticed is that the surface of my skin gets very hot quite often, though I don't feel hot in myself. I only notice it if I happen to touch my bare skin anyway. I keep meaning to ask the next doc/nurse that I see about it, but always forget!
There again, I'm on a lot of other drugs so it might be nothing to do with the blood thinners.
PS When I was put on it just after I'd come out of hospital I got a phone call and a very helpful person gave me a lesson on how to manage the tablets. It was 9am and I was told to take a tablet whilst on the phone and that I should take the next tablet at 9pm. I was given contact details and told to get in touch if i had any problems. Hopefully you should have been given some similar support.