How hard is a penis supposed to get?

Stupid question. I’m with my husband. We’re both 26. He’s always had some trouble making me orgasm. I always blamed myself. Then it dawned on me. Is he not getting hard enough? I’ve had partners before but it’s been a long time and I try not to focus on it. I feel really bad bringing this up because I don’t want to compare him to others. I just want to know what’s wrong. He can get erect and just hard enough to have intercourse. Like shaft is kinda hard but the head doesn’t get hard. Like if I press on the shaft it’s firm but there’s a little give. If I press on the head, it’s totally squishy... When we have sex I don’t really feel much, and he’s average sized but to me it feels much smaller than he really is. Sometimes when he orgasms I can feel him get really hard for like 5 seconds, but no way is that long enough for me lol...So I guess my question is: isn’t the whole thing supposed to get like really hard for the whole time?

Ps. We had an argument about this earlier today. I’m at a loss how to address this without coming off as offensive. He says there’s nothing wrong and this is the way he’s always been and I’m just looking for problems. Is he right? Maybe I’m just over-reacting... I just wish he could make me go.

Any advice is helpful please