Anyone else experiencing this phase with 5 yr old?

[jjibin]

My 5 yr old son has recently been waking up at night sweating and shaking. He screams and isstill  shaken even  a few minutes after i wake him up. He has weird nightmares. What i am concerned about is is this common? He has these nightnmares 3-4 times a week. Mostly they r that some monsters ate my husband and I and he is left alone with his baby brother. Or that i 'forgot' him somewhere. Any advice would be great!