Adjustment of Status - I-485

Hi guys, this forum is the best. I just started this process. I'm on NY and my office is Jamaica Queens (we sent package to Chicago)

So far this has happened:

-Package sent 01/09/2017
-Package received 01/14/2017
- PD DATE 01/17/2017
-NOA for I-130, I-485 I-765 received by mail 01/30/2017 (No text/email) (Day 13)
- Bio appointment received 02/06/2017 (day 20th)
- Bio will be done 02/17/2017 (Day 31st)

I'm really anxious... and now I have a question. I think maybe we could receive an RFE for my husband Affidavit. Thing is that on 2015 (w2 we have sent), he started his job on June, so he only reported 26K on 2015 taxes. For 2016, we didn't submit w2 or tax returned bc we mailed it on January 9th... but we submited his paystub showing that he earn 4k. Do you guys think that for that 26k on 2015 they could say that is not enough?
HousEhold is just him and I... I truly hope that won't be a reason for them to reject o delay my process.
Also, I'm a f1 student overstayed, I didn't finish my english course so I don't have a letter from them that I finish this studies. I had to quite bc I couldn't afford it so I start to learn english on public library. Would this be a problem maybe? I'm so scared!

Thank you for all your posts!