In young, otherwise healthy people who are very physically active, broken bones are not entirely uncommon. For example, it is common for those who play contact sports to get broken bones, and this does not necessarily mean that there is anything 'weak' about their bones; the breaks are just an unfortunate side effect of the injuries that they have sustained.
However, every case of recurrent broken bones at least deserves a good checkup by your primary care doctor
. Although most cases of multiple broken bones are not related to a medical problem, as I said, there are some medical conditions that can make the bones weaker. For example, people who take steroid medications for inflammatory conditions are at higher risk of osteoporosis and breaking bones. There are also some genetic conditions that predispose to broken bones, so your doctor may ask you about your family history.
If nothing turns up, you should be reassured that this was probably just bad luck. Nevertheless, your doctor will give you some advice on how to promote good bone health, such as by increasing your dietary intake of calcium. If there are concerns, your doctor will probably want to order a bone density study. Please talk to your doctor soon!