Bruising??? Tmi warning

Ameliasmom
The past couple of weeks I've had random bruises pop up on me... Like my arms my legs and today my butt... I haven't feel, or bumped, nor have I been hit with anything... Idk how or why this is happening... What do y'all think it is and do y'all think I should goto the doctor about it??? (The picture below is the one on my butt)