If you train long or hard enough it’s more than possible to get an injury. Injuries can be a minor such as a muscle sprain or they could be a major such as an MCL tear. If you develop an injury be sure to assess the severity of the injury from a licensed doctor before attempting to continue exercise. They should be able to provide further insight into how severe your injury is and how much time it should take to get back to normal.
If you’re given the approval for exercise, you should first look into regaining your ROM (range of motion) in the affected area. This can be accomplished by stretching, mobility routines, CARs (controlled articular rotations), or PAILs (Progressive Angular Isometric Loading) and RAILs (Regressive Angular Isometric Loading). These are great to do as a warm up to prime the body for exercise and should increase ROM long term.
Muscular injuries typically occur because of lack of strength from a supportive area. One of the best ways to avoid reinjury in a given area is to find your weak points and strengthen them. A few areas that are typically undertrained are the hamstrings, abd/adductors, low back, and VMO (vastus medialis oblique muscle or medial quad).
Once you get back into the full swing of training, usually the last hump is the mental aspect of pushing past the limits you may have put on yourself because of a past injury. Take your time rebuilding your strength and slowly reintroduce your body to heavier loads. This will allow you to create a strong foundation and reestablish trust in yourself before attempting bigger lifts.
Hope this helps and please reach out if we can help you overcome an injury!