Slow Fermentation (Brewer's Best Dunkelweizen)

Hi! It's been about 4.5 years since I brewed my last batch of beer and after too long, I decided to get back into it. I used a Brewer's Best Dunkelweizen kit and I brewed the beer a week ago this past Thursday. It never had the highly active bubbling in the airlock that I'm used to seeing when making ales, though there was some slow and study activity. My original gravity reading was 140 and it's been fairly steady at 120 for the past 2 days or so. Here's a quick rundown on the process:

I used a new yeast as the kit was old (purchased about 3 years ago), and it was a WyLabs

I pitched a new yeast--WyEast Wheat after the wort was at approx. 72 F. The only snag I ran into while prepping the wort was that my pot is only about 2.5 gallons, so I it does typically mean my ABV is lower than if I had a large enough pot, but I didn't think this would impact the fermentation.

Anyhow, the beer has remained in my basement where it's about 72 degrees, but it's off the floor (so it's not getting too cold). Last Tuesday (after seeing little change in gravity), I pitched a second yeast (Nottingham Ale yeast) to try and get things going. It's moved down to 120, and that's where I am now.

When doing my readings, I've noticed there is some slight carbonation and lacing, and the beer smells and tastes fine (no funkiness!) albeit a touch of malti-sweet from the unfermented sugars (though it's less pronounced now).

I don't want to bottle them now if they'd likely blow up! And 120 gravity just seems much higher than I've ever bottled before (110 is usually where the highest from what I recall). Any thoughts on where to go next?

 

My apologies on not being specific enough on the Wyeast--it was the Bavarian wheat. Do you think it would help at all to add some additional fermentables (either dry and liquid malt extract) to help pick it up? Otherwise, it would just end up being a weak beer, correct?