UFOs seen following the ISS

I was out watching the sky last night, while getting some exercise. I saw an object and I immediately checked heavens-above.com to identify this object. I saw that the ISS was still scheduled to pass my house yet, so I went back outside to make an half-hour observation. Sure enough I saw more objects pass over my house. I checked the time but didn't write it down. Here's approximately what I saw:

00:36 - One object moving north - at this time I went inside to check the internet to try and ID this thing
00:43 - Deja Vu; one object moving north, same trajectory and brightness as the previous object
00:45 - Possibly the ISS, moving north, was dimmer than previous objects, appeared to move into Earth's shadow
00:54 - Object travelling ESE, appeared to enter shadow
01:00 - Object moving almost SW

Again, I didn't write the times down or anything, these are approximate.

Here are my coordinates: 43.3777°N, 79.8399°W

My question to any sky watchers: How common are human satellites seen travelling together in groups or in succession over the course of, say, fifteen minutes?

I thought satellite trajectories are carefully calculated in order to prevent collisions. I saw way too many objects last night for me to consider them all to be satellites. At least one was the International Space Station, but I remember I originally thought the first object was the ISS until I checked online, and saw that it was ten minutes early. After seeing the other four I didn't know what to think other than UFOs.

I don't have any pictures, but can anyone let me know if they too have noticed the ISS being followed by other objects possibly several kilometres apart? I'm still an amateur, and want to be sure if I start calling these objects UFOs.

You might have used this,but if you didn't, it is a NASA applet that lets you track where and when you can see the ISS and other satellites.

spaceflight.nasa.gov...

Stellarium also has a satelite feature and its free to DL. You must get some clear skies where you are. I think satelites can use the same trajectory at different times but, its not something ive looked into lol.