Is the DUI check process in the US unnecessarily embarrassing?

I’m from Germany and two months ago I moved to the US for my job and this evening I worked late, order dinner in the office with a few colleagues and went home, but drove straight into a DUI checkpoint and the cop said he could smell alcohol on my breath and I need to do a sobriety test even though he could see that I had my laptop bag and business clothes so rather obvious I’m coming from work and not a party. Anyways, he got me out, made me stay on the side of the road with legs together and arms by my sides and the warning that if I move it would mean I failed to obey simple instructions and he would arrest me for DUI. He kept me there for about 10 mins time while reading me all sort of laws which contained the word “criminal” a lot…so pretty scary.

Then I was ordered to take my heels off and do the heel to toe walking barefoot, but he was not happy and said they will have a mobile lab setup to test blood alcohol levels. So I got handcuffed behind back and put in a row with 3 men and one other girl and ordered to sit on our heels while waiting for the lab to be setup (as you can imagine, a pleasure to wear a skirt and sit with your bare legs on the pavement, the weight of your body pressing on your legs). Finally after another 30 mins the lab was setup and the blood results came negative.

For people familiar with the process, is this proper procedure or was the cop pushing the limits? And proper procedure or not, is it normal to be put in handcuffs even for 30 mins when you haven’t yet been found guilty of any wrongdoing and you’re not violent in any way?