Hey there!
I'm so sorry to hear you're feeling discouraged, and that you're so sore after your pole classes!
Like you, I didn't move much at all for most of my life. I started pole dance around the same age as you. It was so hard to even trust my body to do what I asked of it, let alone to have the strength for what I wanted to do, or the confidence. It was so hard just to do a spin or to hold the pole properly! I didn't know how my shoulders should go, or what to do with my back to protect the muscles and my sensitive areas.
So, here's my advice:
First, it sounds like your pole dancing class is moving too quickly for you! Withink 5 sessions, I could barely do a single spin correctly- there just isn't enough time given to each move, or to allow your body to adapt properly. You may need to grow your own pole dance slower, because your body is so surprised about being worked!
Second, I would say that your classes are too difficult. You shouldn't be sore for that long! Sore for about a day, the next day after dancing, is about the right amount. You have to remember, you are doing so much with your body when you pole dance! This is very much about strength, and you are working your muscles hard. You don't want to push TOO hard, or else you'll end up injured and banned from the pole for a while! So much more frustrating!
Third... try yoga. While I love pole dancing, and being unable to dance currently because of a shoulder/neck problem (I still need to yell at my doctor on Tuesday about it!), I found that yoga is a great way to move when I don't have the energy, and to stretch my muscles, and get a little strength training in, so that I'm more ready for the pole later on. Also, I do love the pole, but... It didn't help me to trust my body, and it didn't help me learn what I was really capable of, because I was afraid of it! Falling off the pole can be really scary, and some of the shapes we make can be dangerous. With yoga, it's safer, and you're closer to the ground in case you fall. I've learned so much through yoga, and it's helped my pole dancing like nothing else!
I do yoga online, on Youtube, as I can't afford classes... and I'm uncomfortable working with myself that way in a group. I prefer Yoga with Adriene, and you can give it a shot, if you like!
Finally, I know it can be scary, but I really enjoy doing pole dance at home, with Veena's lessons here. It allows me to move at my own pace, and to learn the way I need to learn. There are lots of resources, but Veena's lessons are one of the best I've found out of the very many I have tried.
There are also some things you can do to help with sore muscles. Foam rolling is good, as is massage (if you can afford it). Taking a shower in which you alternate hot and cold (not too quickly, about 5 minutes each) can also help! Stretching properly, and NOT flexibility training, is also really awesome to do.
For reference, I am now 30 years old, I run, do yoga, dance, and lift weights. I'm 200lbs and in the best shape of my life... and I used to never imagine I could do any of the things I do now, ever.
All I used to do was sit in front of my computer, and struggle through work. When I was in University, it was all just sitting, sitting. I was completely unconnected to my body. I had no strength.
It can change, it just takes time, and consistency. And, it takes knowing how much is too much, and how much is too little. You'll learn as you move more, I promise!!