My blood to look abnormally thin however the ratio was like 4:6 serum to red blood cells which seems an abnormal amount as there was practically a small stream of it. is this normal? my blood used to be thick now it seems more watery?

You have unfounded belief. If your blood is thin as water which implies you are severely anemic then you don't have any strength to post this question. You're correct about the composition of blood, 40-45% is made my blood cells and 55 -60% is plasma. That 40-45% portion is made up mainly by red blood cells and when that number drops in half, only 20%, your blood will be seemingly watery.

Your statement is not intelligible. All laboratory results need to be interpreted in the clinical context and the doctor who ordered the tests is usually in the best position to do that. Talk to the doctor who ordered the tests. Wish you good health!