X-Ray Dose Estimate for Lower Back: Understanding Radiation Exposure

[girts]

today I took a x ray for my lower back, now medical issues aside what I want to know is is there any estimate of the dose I received?
just to be clear i don't have paranoia and I know basic physics so I'm not scared but purely out of curiosity because later this year I might have to do things that will give me additional dose, so I want to know.
I asked the doctor but he said that he doesn't know the dose, he said it is being checked and written somewhere but in order for me to know it I must consult the administration and since I did not have time for that I thought I might as well ask here
the x ray was a typical one and it was done in my stomach/lower back area, there were 4 individual pictures taken so 4 shots.

Sorry if this is easily found on internet then pardon my ignorance

 

[Orodruin]

First hit on Google contains a chart with typical doses: https://www.radiologyinfo.org/en/info.cfm?pg=safety-xray

 

[girts]

Pk i will check out, i just assumed this would not be as mainstream as it seems to be