Could anyone recommend something?

Basically I finished the two Ultimate Japanese books Beginner-Intermediate and Advanced. When I looked into the jlpt 3 examples the grammar looked awfully easy, but when I checked jlpt 2 it kinda scared me. I can't seem to find stuff that deals with sentences formulas, ordered a particle dictionary and I possess Japanese Particle Workbook, but once im finished with that I won't have anything else regarding that issue. Should I perhaps use purely grammar books?

I don't know, but you have at least a year until the next test.
What are the exact names of those two books? Where did you buy them (online link if possible) unless it isnt English.

There's an excellent book called "A Dictionary of Japanese Particles" by Sue A. Kawashima which I can highly recommend.

As for grammar, I must recommend the two books published by The Japan Times called "A Dictionary of Basic Japanese Grammar" and "A Dictionary of Intermediate Japanese Grammar". If you are serious about learning Japanese then you gotta get these books!!!

My dad managed to get them for me for xmas by ordering them in through my university's bookstore