Is it normal to worry about baby stopping breathing when sleeping?

My baby boy is 11 weeks old and I am paranoid about him stopping breathing. I am constantly checking him when he's sleeping in the carseat and the pram. I have a sensor mat under his Moses basket mattress which went off about 6 times in his first few weeks of his life. I feel like I am constantly worrying about him dying. During the night last night he was wheezy (think was the mucous from milk) and panicked at first thinking I should take him to hospital. When he feels warm I worry he has a temperature. I don't know how to stop worrying about him.