Mild cramping at 4w3d

For the last 3 days I have been getting continual cramping that feels like really light period cramps and today my lower back started aching.
I've read that this is normal but I've been having this literally ALL day today. 
Anyone have the same type of cramping? 
I had an ectopic pregnancy back in November, and although I don't remember having the same type of cramps, it still makes me worried.