A guy your size has about 12 pints of blood. (If your stats are updated). One pint would be a little over an 8% change. (8.33 to be exact)

Edit donate as often as possible, save as many lives as possible regardless of benefit to ones self. The only way to overcome a worldwide crisis is through worldwide unity Brothers, if you can donate blood, plasma, participate in an experimental antibody test...if you can do anything that might help but cant hurt- step up and lets do all we can as a community to protect our most vulnerable brothers and sisters on this planet and overcome this tragedy

Honestly I wouldn't put much weight on the variation from one donation. There are way too many variables that could over assert themselves (too heavily weighted bias)

What I would recommend you do if you want solid, statistically relevant data is record all of your baseline blood work, then once a baselines is established, donate once per fixed period of time (i.e. once every 12 weeks) and record your post donation values. Do this for 4 cycles (roughly one year) and you will have a solid data set showing you what your average baseline values are, the impact of donating and your average post donation levels . Used wisely, these data points should give you more than enough information on how donation impacts your baseline levels, and how to utilize blood donations to add safety to your on cycle protection protocol while also potentially saving lives.