baby having nightmares ?!

♡ 𝓚𝓪𝓽𝓻𝓲𝓷𝓪 𝓵𝓸𝓾𝓲𝓼𝓮 ♡
My son is 4 months old and this last week, on and off he's been occasionally crying with his eyes still shut and sometimes seems to be in a panic. Only recently does he breath quicker when he's crying in his sleep but as soon as he hears me voice he stops and continues to sleep. If that doesn't work I either snuggle him up again or gently stroke his forehead
Do you think these are nightmares he's having ??