Today I wanted to sign in to Adsense, but it directs me to blogger. I have a blog there, but on a different google account than my Youtube channel. Is that an obstacle?>
And more general question? How to start earning money on youtube (ad-wise)?
If you truly want to make money, adsense is not the way to do it. Think of adsense as a tip jar, you get a few quarters here and there and every once in a while you'll get something decent.
The best way to make money is to first build up your subscribers, then find something that you can sell them (that's not a dumb tshirt, but something that they can actually use).
If you have great content but no subs (and it's not a vlog), then submit all your videos to places where people can buy your raw footage.
You can also make money by getting tv shows to air your footage (don't go through a company, just contact the show and send them the footage..or like in my case they usually email me first).
There is also product placements that you can get paid to do (checkout famebit for that), but i absolutely hate product placements. It's bad enough that your viewers have to watch ads on yt, don't make them listen to you talk about how great rich chocolatey ovaltine is (now available in slamming strawberry that is rich in vitamins) <<<see what i mean.
Lastly there is video competitions everywhere, find one that is asking for a video that you have already shot/filmed/edited and submit. It's always a long shot, but eventually you will get one that pays off.