They are definitely common signs of crohn's as well as extraintestinal manifestations of crohn's. They can also be a side effect of medications you are on, such as steroids.
I used to get lots of joint pain on steroids and when I was weaning off of steroids as well. Now my flare is under control but I do notice that my body will occasionally get hip pains as well as small flare-like symptoms during that special time of the month, which never used to occur. I have come to accept that our bodies don't always entirely go back to what they used to be before we became ill. Such is life.....le sigh.....
The tiredness could be from medication but it could be from vitamin/mineral deficiencies brought on by crohn's or simply be from your crohn's itself. It is an exhausting disease because inflammation wears down your body. Your body needs to use as much of your energy as possible to fight what it believes is a threat to your system, thus your body channels all of your energy to fighting off infection/inflammation and leaves little for you to move about and get through the day with. Vitamin and mineral deficiencies caused by crohn's can also cause your other symptoms.
Always let your doctor know of your symptoms. With regards to fatigue if you have not had your Iron AND B12 levels tested for deficiency, it is a very good idea to discuss this with your doctor. If you have been on steroids, especially for a long period of time, you will want to get your calcium levels checked as well and maybe ask for a bone density scan to rule out signs of osteopenia or osteoperosis