I'm a little old to answer but have been in similar situation of not having sex for a year then having a lot. The physiological answer is that the vagina doesnt toughen up without sex and penis size is only part of the problem with discomfort from penetration.
Discomfort varies by male partner.... foreplay and male experience makes a difference. You are now more experienced and know what to expect so it may well go much better with a new guy. You are less likely to feel discomfort during intercourse but a couple days afterwards might have slight soreness 'down there'.

More likely you'll feel muscle fatigue in hips or core muscles or wherever you got exercised It seems to be the big taboo still for women but masturbation is good practice for comfort with sex generally including intercourse...by knowing how to specifically instruct a guy or if you prefer...subtly guide him.