after a recent break up ive been waking up feeling sick what can it be?

It sounds like you aren't fully over the last guy and dating a new one is keying you up so your body is tensed up the whole time or you are trying to figure out if the guy is the right one for you to tense you up. One thing is for sure, it's a little to early for you to be dating as things aren't fully at peace from the last one which makes it hard for you to enter a new relationship with a clear head. You are probably doing some comparisons between him and the last guy trying to make sure you don't make the same mistake again. That makes it unfair to the fellow and yourself. To your pain, it's caused when you tense up your back muscles, which already have to have a tightness in them to complete the circle, so that they can press into the nerves leaving the spine that go to the organs. Pressure on the nerves to your stomach causes it to release more gastric acid to cause the pains you are having. By releasing your back muscles you will free the ones that were already tight to help make your pains happen and here's how to do that release:

Back:

(do while sitting on a chair)

Place your left hand on your left leg next to your body. Place your right hand over your left shoulder, fingers over the back and the palm in the front, and firmly pull down on them and hold. After 30 seconds slowly lower your body forward and to the outside of your left leg, keeping your left arm as straight as possible. When you reach your lap remain there for another 10 seconds, then release the pressure but rest there for another 30 seconds. Then reverse your hand positions and do your right side.

For best results relax your body first by taking a deep breath and exhaling then remain this relaxed.

hope things work out for you.

might be anxiety