Completely fine ;) throughout the whole pregnancy lol.. Just as long as its not extreme and bleeding, but you can always make a trip to hospital or call your OBs assistant for comfort.
Random aches and pains are definitely normal. Your ligaments, muscles,bones everything is moving around to make room for baby. I was achy all the way up until I had my baby last pregnancy.
If you start getting pains that are unbearable or if you start cramping and it's accompanied by bleeding those are a couple of things to look out for :)
and if you are ever concerned urgent care, hospital and your doctor's office all have a nurse on call that you can call and ask questions too if you start getting really concerned or you start noticing those things I mentioned earlier like cramping with bleeding