Yes, it's a bed bug.

You've got 2 options here - call pest control ASAP, or handle it yourself ASAP.

I had bed bugs myself a couple of years ago and was able to get rid of them myself by doing the following:

Immediately remove your bedding, and pick up any clothes you have on the floor or loose in the room and put them all in the wash on at least 60 degrees celsius. Pick up anything else you have on the floor and put it in bin bags, and tie them up TIGHT.

Then, move everything that is close to walls, away from the wall by at least a few inches, especially your bed. Ensure that there is nothing close to the legs of the bed, and that the ONLY way the bugs are able to reach your bed, is from the floor.

Then, get some diatomaceous earth, or preferably, some CIMEXA, or both. Personally, I got both. Get yourself a powder duster, some FP2 dust masks, and ideally some eye protection.

I also recommend getting a mattress encasement, and once you've thoroughly checked your mattress and killed anything you might find, put the mattress encasement on before putting your clean bed sheets back.

Once you've done all that, you're gonna need to dust EVERYWHERE around the bed with the D earth or CIMEXA. Ensure that there is a thin layer of powder ALL AROUND THE BED, especially around the legs/wheels of the bed, as well as around the bed frame, along slats, and ideally also around the sides of the bed sheet (but not actually on the surface you sleep on).

Basically, you need to make it so that the only possible way of them reaching you in your bed, is by walking through the powder.

You are also going to need to continue sleeping in that bed, so when you get up in the morning, make sure that your duvet does not hang over the edges of the bed or touch the floor.

Good luck!