While hair does refer to the thoughts that come from one’s mind, when a specific hair style is involved – in this case braids - the thoughts can pertain to a specific issue.
Braids are generally made using three strands of hair and suggest a kind of knotting. The braid thus can represent tying God’s knot, that is, the idea of marriage.
Because you are aware of having your arms up during the process of braiding the hair, it would suggest that you are up in arms about the idea of marriage. The hair getting tangled during the braiding process would imply that you are having difficulty getting your thinking to accept the idea of marriage because the thinking being done is not simple and straightforward. Tangled hair suggests complicating ideas. Hair that is straight and not tangled implies clear or honest thinking.