My first test is tomorrow and just need to talk

As the title says my first test is tomorrow, Ive done mock tests which i have failed an passed with my driving instructor he believes im more than ready i know i can drive well an safe i know i can do all the things required of me to pass. However my nerves now the night before are starting to get a little out of control i feel like i know nothing an i will do things wrong despite there being no proof of that. Im also terrified that if i fail the waiting time for another test is crazy. I just cant get out of my own head is all, I hear people say that its about 30-40mins of actual driving on the test taking into account pulling up on the left etc. Is this true surely i can be safe an drive well for half an hour. I dont know one minute im confident the next minute my body is screaming at me that im not ready any advice would be welcome as its in the morning. Also it being the Easter holidays i now think the roads will be busier which makes no difference but my brain is saying thats a issue.