I found out at 3+5, and it was so early I remember worrying about everything. Even, stupid as it sounds, coughing too hard!
I've worried about it all - exercising, hot baths, having sex, what you cant eat, the chances of MC, signs of MC... Too much discharge, not enough, not "feeling pregnant", getting headaches, is it OK to miss folic acid one day... Etc etc but you know what I've found?
You don't need to worry about ANY of those things. If your pregnancy is viable, it will stick, and to put it bluntly, if it's not then it won't, and there is little you can do to change that as MCs from what I have read are mainly caused by genetic factors completely out of our control.
Yes, smoking and drinking and maybe too much caffeine are out, but remember years ago nobody had any guidance and carried on as normal and most of us turned out fine.
The main thing I have personally found is that avoiding too much worry and anxiety is the best thing you can do. Stay calm and that's the best thing for you and your baby :-)
Try a mindfulness app or find something that relaxes you and read up as much info as you can from NHS sources to make sure you feel you are doing everything you should be.
I hope that helps? Xxx