Things like nyquil sometimes work because they rely on a side effect of decongestants (sleepiness). Avoid all caffeine containing products, avoid excessive sweets/sugars, just now you're likely exhausted so cut back on your exercise (but a short evening workout a couple of hours before bedtime might be helpful). I suspect you're overstimulated (new location, job, worries, etc. -- and your mind just cannot catch up, so interrupts your sleep), so give your mind some much needed daytime breaks.
I suggest: one short (5-20 minute) nap at least six hours before bedtime (ideally, just after lunch or instead of an afternoon "coffee" break); one daily meditation or quiet time break of 15-30 minutes (where you just sit comfortably, try not to follow any line of thought, and let your focus center on slow, even breathing) -- the ideal time is when you've not eaten recently. If you feel too 'wired' to try this, you might first work on a puzzle book for ten minutes or so. The first few times you try this may be challenging, but please persevere, the benefits once you get the hang of it are considerable.
Avoid 'blue' lighting a couple of hours before bedtime (that's lighting from CFLs, fluorescents, LEDs, PC/TV screens), or at least wear yellow tinted or regular sunglasses during those hours. Incandescent lighting's fine. ((the blue component of lighting suppresses melatonin production, which is our sleep hormone))
I agree with scalpmassager. but I would add....You could try Melatonin 3 mg tabs (OTC) to take at night before bedtime. Try to employ good sleep hygiene too. That is, prepare for your sleep by eating small evening meals, turkey preps are said to be a good source of the amino acid tryptophan. Try a relaxing hot bath with Epsom salts and lavender oil. A glass of milk is good practice as well. You may need a professional to take you further but these practices have helped. Find a TRUSTED friend who may have some good suggestions....at least to help you put your own concerns in a proper prospective
Insomnia can be very difficult to handle but don 't lose heart don't allow it to whittle away at your inner self!
Melatonin works better at 1mg than 3mg for most people, so I'd start with that dosage. This is one thing that's better with less, though people do differ. I agree with the above that this is a good remedy to try. I don't agree with the milk -- it is high in tryptophan, but it's also difficult for most people to digest dairy, and eating anything right before going to bed triggers the digestive system, which can interfere with going to sleep and staying asleep. Another remedy that might help is a homeopathic remedy called Calm's Forte. Be careful not to over-exercise -- don't want to injure yourself. As for meditation, don't meditate anywhere near bedtime, it can be very invigorating, but I agree it's a good thing to do, but I don't think most people get the most out of it by learning it by themselves or from a psychologist. Best to learn it the old-fashioned way, from a Buddhist teacher. Something in the transmission helps you to learn to let go. Good luck.