How do the first 100 matches work?

Hi!

I have a question. Basically the title one.The reason I ask is the following one: I had an account to play with my local friends. Over 3 years I went down with them – from Archon to Herald. It's fine. They just wanted to play ranked for some reason and I said yes.

Now I didn't want to try to level this account up. That would be a lot – A LOT – of work, even with a 60% winrate. So I created a new Account. On the first 25 matches everything was pretty even, won a tiny bit more than I lost. Then – wow… shit got real. Now I am at about 50 matches with a winrate of 33% basically I just loose 5 or 6 matches straight, then sometimes a win or two, then again 5 or 6 matches lost. This is pretty consistent.

Now… I have dotaplus installed, this addon you might know that shows you a lot of stats. There are also smurfs displayed an who is in a team with whom. I observed that I play against A LOT of smurfs or on my side is a team of 2 and on the other side a team of 4. Sometimes my players start to standing around in lane, idle, doing nothing, waiting to be killed, like a beginner, not knowing what they do. I must also add that I usually win the lane, often easily, have one of the highest net worth in the game (as Juggernaut), get most kills on my team as a support WD… most of the time Dotaplus, stratz and so on give me a positive impact. Still, the others are better and some opponents really have an admirably higher skill than me.
The games I win are usually really hard to win. Fe. as a Jugger I was top net worth, most dmg, most kills, then 4 enemies came, then my team. Or as a Natures I did 30k dmg to buildings. Both were ofc extremes and on 1 match I got carried by my team.

TLDR, now my detailed question: Does dota recognize that this is a second account? If so – why am I up with this 'smurf' when my old account is only herald? Why am I up against so many better players (than me and my teammates) in the unranked matches? How does these first 100 games work? I mean… with a winrate or 33.3% you are either out of luck or the matchmaker thinks I should be good enough to even out the odds – which I am not. Usually – as far as I know – the first 10 to 20 matches should do the calibration for unranked MMR.

I'd be really unhappy to loose like 40 games with only 10 wins during the next 50 games. Does Dota want to force me to play the other account. I am really curious.

Edit: I don't ask about how to improve (I know there is a lot to improve but that is another topic) so I won't provide matches. I am only asking about the matchmaker since this has some real consistency now. I am not complaining about my teammates nor about me or a hero. So spare me a gitgood or some other advice, thanks. Only asking about the matchmaker.
Sorry for the long text btw.