Which blood components to check? Non-(less-)invasive methods available?

Hello,

i wanted to ask for which blood components I should do a blood check and for which ones I could use a non-(less-)invasive method. I live in Germany.

I found this device for hemoglobin: http://www.mbr-optical-systems.com/en/haemospect-product.htm
I found this company that seems to offer a lot of tests with only a small cut in the finger: http://www.theranos.com/test-menu?ref=our_solution

The first company is from Germany and the device doesn't seem to be for home use (?) and only for hemoglobin, the second only provides services for everyone, but only in some regions of the USA, so it's probably not that interesting for me.

Is there anything else? Any device, center, etc.?

I'm not certain there is any need for you to be tested.

I know it's embarassing, but don't underestimate my ability to avoid a blood extraction in any possible way.   They diagnosed me with thalassemia when I was a small child and decades ago, so I don't really know "where I am" at the moment, what my blood levels are. It's just that I get older, it doesn't get better, but at the same time I'm expected to (and want to) deliver more (work, studying). The constant fatigue is an issue and causes strong depressions. I just don't believe they are coming from anywhere else. I'm really not a sad person, just tired. I only get sad about not being productive in the way I want, e.g. I'm really interested in a topic at the university, but the only thing I can think about is how I can stay awake. I sleep enough and well, but my body simply doesn't fully "recharge" and after a while I feel "depleted" and the small "recharge" via sleep is not sufficient anymore. When this happens, I also avoid even simple conversations, because it costs too much energy I don't have.

I want to know what I can change and what I (probably) can't.