Well, it’s not just you. This happens with everyone. And it’s quite common. Also called red-eye effect! See, the cause is rather simple. Our eyes’ pupils are red in color. When camera’s bright flash falls on it, it penetrates through the pupils, falls on the fundus and then reflect back to the pupil and out in the open to the camera’s lenses. And when it happens, our eyes appear to be red. The more the blood in our pupil, the more our eyes look red.
This generally happens in low light environment. So the easiest way to avoid this is to take pictures in decent lighting. Or you can take picture without the flash. These days, cameras also come with red-eye reduction capabilities—you can use that.Although this doesn’t guarantee the result you want, you can try looking away from the camera lens to avoid Red Eyes. Also, you can try using bounce flash surface such as white cardboard, wall or ceiling that can change the direction of the flash, ensuring only moderate amount of light gets in the eyes.