Co-sleeper crib safe sleeping advice

I’m hoping you can help me please.

My 9 and a half week old son has recently outgrown his Moses basket which he was sleeping in in our bedroom every night since birth. We therefore purchased a co-sleeper crib (Red Kite Baby Nebula) for him to sleep in, however we can’t fit the wheels under our bed so just use it as a stand alone crib instead (always with the moveable side panel up), but pushed right up against the bed so he is close to me and I can see him easily through the mesh window.

However, he wriggles and moves a great deal in his sleep and when I’ve woken up at times he has been lying diagonally across the crib, with his head in one corner, and he often bangs his head against the sides.  Just tonight he had managed to roll onto his side.

I have been losing sleep and waking up regularly to check on him because I’m so worried he will move in his sleep so that he is lying with his face pressed against the side (which isn’t the mesh side) and won’t be able to breathe if his nose is touching the side.

We never put anything in the crib with him, always put him to sleep on his back and he now sleeps in an armless ‘grow bag’ baby sleeping bag during the night so he doesn’t wriggle under the covers in his sleep.

If I wake up and find him lying with his head close to the side I always move him back to the centre of the crib but I’m extremely anxious that when my husband and I are asleep he will end up with his face pressed into the side and I just don’t know how to try and avoid this happening.

We have a beautiful wooden cot in his nursery, which is just next to our bedroom, all ready to go when he is 6 months old (we have used it for every nappy and clothes change since he was born as a changing area) but I know we’re not meant to put him in there to sleep until 6 months of age due to the risk of SIDS.

I would be extremely grateful for any advice you can please give me as to what we should do regarding this. 

Many thanks