No pain no gain?

So I mentioned that my SIL is in town and how we wanted to get together to exercise. We had one week free gym memberships, so we've been using those this week to work out. The first day we ran a 5k and I didn't do too bad for not having run in two months. The second day we ran about two miles, lifted weights, and did an ab workout. It felt good to do, but today I'm feeling it. All those muscles I've been learning about this semester are feeling the love. lol It's been fun though and I find that I've really missed running. It's been a positive way for me to release some stress and frustration this week. One of these days it would be nice to have a gym membership all the time or even a personal trainer.