My 1 year old baby has been waking up several times during the night and just strains his body and cries for a few min it's been happening for 2 weeks?

Reflux?: Was your baby very spitty as an infant? Any new foods or milks introduced recently? Acid reflux often flares at night, causing a burning and choking sensation, triggering arousals from discomfort. This is something for you and your pediatrician to consider, but a history and physical is warranted to evaluate for other causes such as ear infection, etc.

Likely normal: Baby is likely experiencing normal sleep/wake cycles. The crying and flexing are the baby's attempts at self soothing even though he's not fully awake. If episodes last a few minutes and baby can put himself back to sleep just monitor. However, if baby develops signs of illness, is excessively sleepy during day, not feeding well or behavior changes, call your pediatrician right away,

Teething,acidity: Try giving tylenol (acetaminophen) at bedtime for a few days.Go over any new foods he is eating.You can give him some mylanta or gas drops if he is gassy.