Your post sounds like me when ds was this age. If feeding/rocking gets her to sleep then do it.
I had the problem that neither of these worked regularly. He would just cry and cry no matter how much you soothed etc. I shouted at ds many times though I'm not proud of it but I was just so exhausted and lonely. Dh used to get tearful hysterical calls from me all the time so please don't feel bad about doing it once.
I will tell you what did help me eventually a bit and it had nothing to do with co-sleeping which I also tried but if anything it made things worse.
Ds was basically overtired and overstimulated from too much going out and lack of sleep. He NEVER slept more than 30 mins when we were out but sometimes slept longer at home.
He was basically a baby who could only take so much stimulation and would then flip out. Even today I look at people sitting in cafes/noisy places with small babies asleep or just contentedly looking and marvel. You got about 30-40min of calm with ds before he would start to agitate and cry. Feeding him when he was like this did not help he just got more agitated. He needed rest but didn't know how to get it and was very noise sensitive.
I decided two things
One - ds needed to get to sleep during the day for naps and I did what ever worked best to get that. I also left him to cry if he slept and woke after 30-40 mins, not for long but for 5 mins or so. Often (though not always) this worked and he went back to sleep.
This did mean getting him to take a nap within 1-2 hrs or waking up and 1-2 hrs of waking from his first nap. Sometimes he had a third nap and then was asleep for the evening at 5.30pm. This was because he was so sleep deprived.
Sometimes I felt like I was going mad as for about a month I couldn't do anything that took longer than an hour out of the house as we had to be back for his naps. After about 1 week he did definitely improve and we had some days which were much calmer. I also let him sleep in a sling on me at home sometimes if the cot really wasn't working.
The second thing I did was accept that ds was crying. If I was pretty certain he was fed, not in pain (I did use calpol sometime just so I could be sure) etc and he was crying and wouldn't stop I just sat down and held him. I gave him my full attention and was sympathetic but did not try and stop the crying. I decided he needed to get something off his chest and my job was to listen to him and not try and fix it
Quite often the crying would stop after a while and he'd be happier or would fall asleep exausted. The very fact that I just accepted his crying also helped me me cope a bit.
I won't lie, it took about 6 weeks but eventually we saw an improvement in his night sleep wakings he only woke once for a quick feed (before it had been 5-7 times between 10pm -5am and feeding would not get him back to sleep for most of those) and then he just seemed to have more days where he was happier.
He was a baby that needed a routine but couldn't sort one out for himself. After 1 year he did improve considerably though and he now sleeps much better though he still isn't great.
Please don't worry about having the patience for a toddler. I find this stage soooo much easier. I do still get a bit annoyed/irritated but nowhere near as much as I did when ds was a small baby. Despite ds being more into things, more tiring and beginning to have tantrums I find this stage a doddle compared to his babyhood. You will probably find that once you get through this the toddler stage will be fine.