Quick little question

So recently me and my so started doing walks every night after he gets off. Which is great because he encourages me to get up and moving. I've been having pretty intense Braxton hicks but they are not regular. When we walk I have intense back pain and extreme pelvic pressure like something could be happening but when the walk is over I lose it all.  I come in the house and usually lay down and fall asleep. 
So the question is am I wasting my time. When I feel the pressure should I keep walking until I get things started? Or just keep up the daily walks and see what happens?