Seven months into twist and rip/back comb and my hair looks like a mop head and not at all like dreads..
That's about how my hair looked at seven months... just sayin'. :P
Check out my timeline, we have similar progress about that time. The washing and tams and stuff may help speed it up a little bit, but ultimately I truly just think it's a matter of everyone's hair dreads differently, at different speeds. Don't let it discourage you. Once you have some killer progress you will be so proud of it because of the patience you had and the amazing way it all forms that it won't even matter how long it took.