I could just be crazy but..

So my husband and I already have two kids, and I haven't been on birth control for a few months due to insurance issues. But I ovulated no less than two weeks ago and my husband accidentally came in me on one of those days. The crazy part is I literally already feel pregnant. Not sure if it's just paranoia or if I really am showing symptoms. But I've been very irritable, had a lot of back pain, indigestion and nausea. Has anyone else noticed symptoms that early during a second or third pregnancy? I would test but I really feel like it's way too early to test.