IMO Pinterest is pretty good. I would not judge it based on just 2 days worth of following for a start. Pinterest is slow and people following you back on Pinterest is even slower. You need to have a nice full profile with plenty of boards. Then you also need to pin all the time. I set up about 100 pins a day to go out on each account. I rarely bother to follow on there because I use group boards which do generate some decent traffic. Its far from instant though most of the pins take months to gain traction but when they do and you have done it for months on end the results catch up quick.
I would say that's very normal figures for the amount of time that has passed. When I follow I tend to try to follow people who have lots of pins which shows they are active. They normally have more followers too so its worth my time and I get better results from the low following limits on Pinterest.
I used to use an app called tailwind for promoting and scheduling pins, there is a bloody good video on YouTube which is about 10 minutes long by an internet marketer using it. I used to be an affiliate of theirs but funnily enough I stopped just two days ago. Sadly it was producing the revenue that some of the things I promote do so I stopped but as a user and as a tool I would recommend it to people looking to get the most out of group boards. I could set up 100 pins on each account to go out throughout the day to all the group boards i selected and then I could randomize it so it looked pretty normal if you looked at the accounts pins. the video on YouTube explains that better. I posted about 50 promotion pins or pins to items in my shops and the other 50 were fodder just to look nice to random boards of my own to grow the account. I still see results 7-8 months on, i get hundreds o repins each week because i made a few pins for a week 8 months ago. all it takes is for a few pins to go viral on there and the account gets lots of organic growth. I say lots i mean more than it would normally, its far from lots.
Just get access to a ton of group boards, automate the pinning and the results will speak for themselves. Pinterest is very much not dead! The type of thing you are trying to promote on Pinterest makes a HUGE difference too, some things do very well by default. I would not give up on it yet, its not that much work honestly.