Macbook gets hot for no reason

My MacBook pro (Retina, 15-inch, Mid 2015) has been getting hot while doing simple tasks. I can't even play music on iTunes without it getting hot. I've tried everything I can online to try to fix it but nothing seems to be working. I haven't even had the computer for a year yet and I'm very concerned about it.

I've tried checking the activity monitor and I'm only using 4gb of ram (which is how much it's always used while idling) and has 12gb free. I'm also only using 5% of my CPU.

I'm giving it plenty room to breathe. I have it sitting flat on my desk with plenty of room around it. I've even tried getting one of those fan pads to put underneath it (plugged into a different power source and not the computer) but it'll still get hot.

I've tried using compressed air to clean out the fan. Didn't make any difference.

And finally I'm on the latest update (10.13.4). I've had this issue since a prior update and it is not caused by this update.

I feel possibly this issue is coming from the fact one of my homework assignments (messing with a photoshop document that was over a gb in size) required pushing my computer to it's limits. It didn't start getting hot doing nothing until a bit after I was working on the assignment but it's the only thing I can connect to the issue. What can I do to fix the overheating issue?