IM, go get that gym membership if you think it'll help! I go to a gym in the mornings which has been my saving grace- I actually go! Haha. The scariest part is signing up because I always build it up in my head to be a bunch of scary meatheads laughing at me behind my back as they take my money and assume I won't actually use their services.
Turns out that the people there are perfectly nice and I'm not intimidated at all, actually I've belonged to probably 5 or 6 different gyms and I've never had a bad experience. Go for it!