It sounds like standard latent phase of labour, which can ramp up, then be knocked off by adrenaline of going into hospital or even something as minor as a change in activity. Hang in there and don't be too disheartened. Try not to focus on the 2cm thing if at all possible. Your body is trying to labour, it's just not quite there yet. Rest when you can, eat, drink, wee regularly (very important) and move around when you can.
If you've got a TENS, get it on and working, if not, ask the hospital if they have one for you to lend. If they don't, try a warm bath or shower and try some paracetamol and a lie down in a dark room, sometimes a nice warm cuddle with partner may help increase your oxytocin levels (and if not may help you to relax and cope with the pain a bit easier).
Things like nipple stimulation or snogging your partner can also help boost the oxytocin (your labour hormone), but that's a personal preference.
If you're struggling with pain, try to visualise a safe place or a favourite place which makes you feel safe and relaxed and as each contraction builds, imagine you're walking toward it, as it fades, imagine you're walking away.
Stomping can also help - as you feel the contraction build, stomp your feet (or rub them together if lying down) hard. What this does is distracts you, keeps you mobile but also blocks the signal you'll get from your womb as you have more nerve endings in your feet and your brain won't be able to process both pain signals. So stomp stomp stomp hard and focus on the sensations in the soles of your feet until contraction goes. If you can, stomp in the shower as the warmth will help and the water under your feet will add an extra sensory distraction and your brain will focus on that rather than the contractions.
Try a hot water bottle or a bit of massage (a tennis ball can be a great help) and remember to sigh out slowly as you breathe - make your out breath longer than your in breath and try to drop your shoulders away from your ears as you breathe out. The trick is to relax when you can and distract when you can't relax.
Hang in there, you can do it!!