The constant worry is completely normal, Italian! It also doesn't go away after you give birth, you just transfer it all to fretting over the wellbeing of the child you've brought into the world.
The good news is that you will get used to it being a constant companion, then slowly but surely realise that the worry isn't actually worry; It's the motherly love for your baby. :) It's amazing how it starts from the moment you see the line on the test!
As long as you've had no bleeding and have no pain that can't be touched with paracetamol then there is likely to be no cause for concern. Slightly sore breasts and just a bit of tiredness/nausea/dizziness is absolutely normal for 5 weeks.
A bit of cramping is also perfectly normal. Everything has to stretch and rearrange itself. Also, the chemicals your body is producing will be softening the ligiaments. You may have accidentally pulled a muscle in your lower abdomen, if you've been lifting a suitcase?
Have you been to a booking in appointment with the midwife yet? I'm guessing not if you're abroad. Make sure to arrange one when you get back, then mention any concerns when you meet with him/her. All the MW's I've dealt with have been lovely and really helpful.
Until then, try to relax! [stealth hug]