Low brake fluid in the master cylinder reservoir can cause the brake light to come on when turning, try checking the fluid level. The steering wheel wobble could be caused by loose front suspension components, loose steering column components, or a wheel/tire problem. This sounds like a safety issue and you should have the problem checked by a qualified technician as soon as possible!
Also may want to check the front (between rad & eng.)motor mount, they tended to give a 'wobble' sensation (like the wheels are loose) , at take-off , under mild to moderate load. And don't take so long to fix it next time!