what should i do and what is my rights?

got pulled over for speeding found marijuana in my car took my phone and car untill he gets warrants told me to come back the next day to try and get me to give him more info said if i dont tell him what he wants to hear that i would be able to take my car and phone home that day. he stated that if i dont tell him the info he wants to her that i will get a dui and a felony charge for evrything he finds on my phone. they never took blodd or anything .he had searched my car prior to getting a warrant or my permission then said the warrant was so he could hold it and go over it when ever he gets time he had removed my phone from the car.also had let me use my phone after he "seized" it and let me get my drink out of my car after it also was "seized" but wouldnt let me get my house key.