It is a matter of waiting really if you applied on 18th and you have not had your application returned which takes about 2 to 3 weeks we are well beyond that then it should be in a pile with a CO. Give it another week the Feb batch AoR is slowly filling up but it does not work on when they received your application, as people in the middle of Feb started getting AoR first, I believe it is in how they arrange the piles once they confirm all necessary documents are available.
Again short story it is too early to worry give it a few more weeks at least