When a California resident like you receives a blow to the head, it’s possible that you may then suffer from a concussion. Concussions can vary wildly in severity, intensity and duration. Because of that, the recovery time can also differ vastly from case to case. In some individuals, predicting recovery can be difficult.

Healthline takes a look at the severity ranking of concussions. The symptoms are ranked from grade 0 to grade 4, with 0 being the most mild and 4 being the most severe. A grade 0 concussion involves difficulty concentrating and headaches. A grade 4 concussion means that you have lost consciousness for longer than a minute straight.

Grade 0 and 1 concussions are typically the easiest ones to recover from. Within a day or two, limited physical activity and more strenuous mental activities can be picked back up again. However, you should still be careful with your recovery. Grade 2 sufferers may need several days of rest. Meanwhile, if you have a grade 3 or 4 concussion, it can take weeks to properly recover.

Though symptoms in all categories may begin to fade after a few days, it’s important for victims to refrain from resuming your normal activities until after all of the symptoms have gone. Jumping the gun and moving right into your usual schedule just because you feel a little better can potentially cause parts of the healing process to be undone. A doctor should be there to monitor your health as well, since concussions can be fickle and it is hard to predict whether one will get better or worse.