How can I get this out of my hair?

I had a lot of buildup in my hair, so last night I mixed a water/baking soda mixture and put it on my hair. I rinsed it out and shampooed normally, but then when it dried, there was still tons of residue from the baking soda on my hair. Now it's all crunchy, it tangles really easily, and you can just feel the baking soda on it. I tried to rinse it out really well, but I couldn't because the water pressure wasn't that good. How can I get this residue out of my hair?