Pregnant and fiance started watching porn

This is very long so if you read it all I appreciate it.

I don't have a problem with porn, I've watched it in the past so has he when we was younger/single and we have also watched it together on occasion. But I'm 17 weeks pregnant with our second baby (our first is 13 months old). I got pregnant again quite quick when my daughter was just 9 months old I had just felt ready to restart my fitness after putting on more weight than I'd have liked to. Then I found out I was pregnant again, we was talking about having another baby so wasn't really being careful, we just didn't think it would happen so quick as my periods weren't back to normal I had only had 2. Anyway I had a bad few weeks accepting it and getting used to the idea and was really upset about my body when I hadn't gotten back to 'normal' and upset about the fact I'm going to change all over again. Anyway he reassured me said all the right things we are now both super excited and everything is fine.

With this pregnancy I've been super tired so much more than last time so I take naps in the day when my daughter naps and I go to bed early. I try to keep our sex life active we are still having sex up to 4-5 times a week and for me that's more than enough but sometimes I'm just so tired I fall asleep as soon as my head hits the pillow which infuriates my fiance. He wants to have sex every single night. Like, I need a break sometimes. He so gentle and makes sure I'm comfortable when we do and never forces me when I say no but he goes mardy like his pissed off at me and I feel bad. But I don't do it just to make him happy because I know i won't enjoy it. But when we have been having sex recently he's been asking for things like he will blurt out he's going to get something big and put it in me and I'm like no. Or can he put it up my bum and some other weird stuff (all of which ive said no to, 1 because im pregnant and dont feel comfortable with it and 2 because we have never discussed anything like this before) this all came out the blue. He's started staying up really late he never used to let us go to bed separately always together now he will gladly stay downstairs playing his PlayStation all night or he will come to bed wait till I'm asleep then come down and sleep down here. Anyway I was on his phone the other day not snooping just watching Snapchat stories (we both freely go on each other's phone) and I saw he had one of a girl posing naked and doing things? So swiped across to see if they had communicated and he had he sent her a photo (don't know what of) and said hey but no reply from her. Then I thought about the things he's been asking and I went on his search history and he's been watching porn like proper hard-core porn! Which makes sense to why's he's asked me. So I sat him down and we had a conversation, I got a bit upset just about him not wanting me for me anymore and wishing he had someone that looked like them and does the things they do and i told him that will never be me. And I asked him why he's been watching it he said that he just wants it but he knows I don't so watches it. He's not a fan of masturbation so just watches it. I asked him if this is why he's been asking me all these things he said they have given him ideas he said he would never want to be as rough and weird as they are but he would like to try. So basically what I got from to conversation is that he's a bit bored with our sex life and that it's a bit plain which It has been. I'm okay having sex whilst pregnant we was doing it right up to the day I went into labour last time we was literally about to then my waters broke. But I'm a bit more reserved and cautious and dont want to do crazy positions or fast or hard because it's not comfortable plus I'm exhausted most nights. Which he understands but doesn't like it. I said to him after the baby is born and I'm feeling okay again and my body is healed then we will try spice things up. I said to him we can talk about the things he wants to do and I'll tell him what I'm comfortable with trying whilst pregnant (if it's safe) and what will have to wait and he agrees.

Do you think I've gone about this the right way/being fair. I've been thinking about it a lot and think of ways to please him as much as I can without it being a burden/chore on me. And I really feel comfortable discussing this with anyone I know as don't really want them knowing about our sex life.