Urinary frequency at nighttime???

I am 37/m and this is my problem:
I urinate before bedtime, then around 15 minutes later I feel like I have to urinate again. I go and just a little trickles out, then I lay down again. Sometimes this is all, sometimes I have to go again in around 10-20 minutes or so. No burning or anything. I don't have a problem in daytime and for a couple of nights this urge would come every 2 minutes or so. I went about 10 times before I went to sleep. This hasn't happened lately. I've been to urologist and had a doctor feel of my prostate and check urine for infection. He said I was fine physically. I take 2 allergy shot/week and drink 3/4 cups coffee in morn, none after 11am. I have heard of something called nighttime tea, or bedtime tea that's supposed to help but can't find out where I heard it from now that I want to order some.
thanks for your input Tweet