My son went through the same thing. I let him play. He has an exersaucer and I would let him play for awhile before bed time or nap time, then give him a bath and put lavender lotion on him then give him a bottle and rock him. It's lots of work but it helps!
That's what my daughter did. It sucks but there really isn't a lot to do. My daughter fought so bad and would get so mad she would like best herself up!! She'd wake up with scratches on her face and her hair. She would sit and pull at her hair. She was pissed lol. But she grew out of it. Some people say giving rice cereal before bed helps them sleep better but I've never tried it for my kids
My daughter went through a phase at about 4 months were she would just fight!! I asked the dr what I could do she said there really is nothing you can do but try things that may help soothe baby like bath before bed, lotion, massage, bicycling legs, rocking whatever you have to do. My daughter luckily got out of that phase after about 2 weeks...longest 2 weeks of my life lol