Worried we screwed up with our offer.

Recently I posed about my excitement in putting an offer in on our first home. 2 days later, I'm starting to worry we screwed it up. Rural, LCOL town. 3BR, 1 1/2 bath, with detached 2 car garage. Listed for 125K, we offered 120K, seller to pay closing costs and buyer's agent comission, and also contingent on an inspection. I'm not married to those conditions or that price - it's just where I thought it was reasonable to start. We are pre-approved from our lender. I wouldn't think 5K under list would be that much of an issue (4% under asking price). But we submitted our offer on Monday afternoon, and have not heard anything yet, so I'm starting to worry that my offer was unreasonable. The offer expires tomorrow at 5pm - I plan to get on my agent's back tomorrow to get ahold of them and push for an answer. Can someone help set my mind at ease?

EDIT: Seller came back with a counter offer, nothing we weren't willing to accept. So we have a verbal agreement now, and should have a signed contract tomorrow morning!