Would a cold producing mucus cause lower blood sodium levels?

[Emzy86]

My serum sodium came back as 132 (my lab reference range 133-146) when the blood test was taken I was suffering with a bad chesty cold which produced plenty of mucus from nose and chest. I also had drunk 4 glasses of water in the hour before the test and had not eaten as was an early test and food too early makes me sick. Could this have lowered my blood sodium levels? I don't add any salt to my food and generally eat low salt foods. In the week before the test I was taking cold and flu tablets which contained in total 520mg caffeine per day. Could this have all contributed to slightly lower levels? Should I be worried? The gp has said to only add some salt to food no mention of a retest. I feel OK in myself now just the last part of the cold to clear I'm feeling down but thats it. 6 months ago without a cold my level was 134 (still drinking water before test) still with not much salt in diet and only drinking water. I do not drink alcohol and rarely have ready meals.