Flasher indicator staying lit is possibly a bad ground, or a bad bulb, or both on any of the exterior signal lamps.
Tighten the mirror is easy. If loose at the top, unscrew the mirror base from the headliner and remove it. Inside it visible from the top is a flat metal plate held on with 3 screws that press down on the mirror stalk upper ball socket. Tighten those screws all the way snug. Where the mirror glass frame part attaches to the stalk at its lower end, theres an allen key bolt on the front side. Tighten that if its loose there.