I noticed the same thing in March and in April.
In March I used a new conditioner: Profective Mega Growth Deep Strengthening Growth Conditioner. I didn't add oils to it, because it has quite a number of oils included. So I noticed less than two days later, my hair was really dry and strong--even though I oiled it thoroughly before and after pressing. I had to oil my hair several times a week because it was "bone dry."
Then for the next wash, I decided to use a different conditioner: Pantene Relax and Natural Mask. This time I added olive oil to it, even though oils are already included. My hair wasn't as dry and strong as the previous month. However, I had to oil it but not as much as with the Profective conditioner.
Now this month, I decided to clarify with baking soda before washing. I used my Motions Moisture Plus conditioner, and now my hair feels a lot softer and normal. Those other two conditioners did the job, but they made my hair stronger and dryer than normal. I assume they are protein conditioners.
I decided to add coconut and peanut oils to the Profective conditioner. Hopefully, my hair won't be as dry next time I decide to use it.
I would recommend that you clarify with baking soda and water thoroughly then try a moisturizing shampoo if you're not already using one and a deep moisturizing conditioner.