Dog is disorientated and unbalanced!?

2 days ago my dog fell off the bed.Im not sure that this is the reason for her being unbalanced coz I think the disorientation might have caused her to fall off the bed. She now is walking like she is drunk.very unbalanced. She hasnt got any pain that Im aware off. She eats and drinks water. urinates.everything seems normal. she is a boxer and is almost 8 years old. She is also an inside dog and I feed her good food for older than 7 dogs. Another thing is, I found a tick on her about 12 days ago.could this be it. her gumms are normal colour. please help.