Why you did not take your profits on the 38 call? I am guessing it is because you wanted to limit the upside risk on VXX. Did you consider other (partial) alternatives such as selling a put at strike 33, and use the proceeds (of part of them) to buy OTM calls?
The 33/38 call spread is like buying a 38 put, and selling a 33 put, which can make you net premium, and time working against you if VXX does not move.