Back spasms

around 2 weeks ago I had my first ever back spasms, I had never felt back pain like that it was debilitating and happened bending over to put down a box that weighted make 20 pounds, it took around a week before I felt normal again, but today I was running errands amd doing some odd jobs around the house just very light lifting but a decent amount of bending, I had to run to the grocery store for a few thing and I bent down to get something out of the refrigerated area and all of a sudden bad pain again, now I'm spasming again, should I have been more careful since I was a week out from recovering from the first bout or is this something I have to look out for always?