That's not how Ottomans are played on line. The first building is usually a trading post, then a barracks as near the enemy town as possible. Age up to Colonial by at latest 4 minutes, send 5 janissary shipment, build 10 more janissaries at the barracks and attack, at about 6 minutes. Probably the enemy will have something like 8 crossbowmen and 1 outpost to defend; the janissaries easily beat them. Next shipment 3 hussars, which go looking for stray villagers, and janissaries constantly coming out of the barracks.
The non-stop stream of janissaries is hard to stop. However, if the rush fails low-level Ottoman players tend to give up - they've spent enormous quantities of food on janissaries, are capped at 25 settlers and are overtaken by their opponents.
That's my experience, having played against Ottomans about ten times, and it's borne out by comments on these forums from lots of other players. It seems similar at the higher skill levels, except for the bit about giving up if the rush fails!
It strikes me as a very boring way to play, far too stereotyped, and I won't use Ottomans because of that. I've tried Dutch and Spanish, and am debating British or Portuguese next.